Physical vs Chemical Changes

CONCEPTUAL

Science›Matter & Materials|Ages 11—13|ID: mt_1hgck6ucII

Distinguish between physical changes (reversible, no new substances formed) and chemical changes (new substances formed, often irreversible), using conservation of mass to understand both types

Mastery Evidence

Classifies given changes as physical or chemical with justification
Explains what conservation of mass means and why mass is conserved in chemical reactions
Names observable signs that a chemical reaction has occurred (colour change, gas produced, temperature change, precipitate)
Explains why dissolving is a physical change but burning is a chemical change

Assessment Prompt

“If [child] dissolved sugar in tea versus burnt toast in the toaster, could they explain which is a physical change and which is a chemical change — and what test would show that mass is conserved in both cases?”

Curriculum Standards4 alignments

MS-PS1-2Next Generation Science Standards (NGSS) Middle Schoolcodes only

Standard code — full text not included in this dataset.

MS-PS1-5Next Generation Science Standards (NGSS) Middle Schoolcodes only

Standard code — full text not included in this dataset.

KS3.Sci.Chem.AEC.4The national curriculum in England

Conservation of Mass

conservation of mass changes of state and chemical reactions

Science · KS3

KS3.Sci.Chem.PIS.5The national curriculum in England

Physical vs Chemical Changes

the differences between physical and chemical changes

Science · KS3

Prerequisites5

The Particle Model
softAges 11—12
Conservation of Mass
hardAges 10—11
Irreversible Changes
hardAges 9—11
Reversible Changes
hardAges 9—10
Atoms, Elements & Compounds
hardAges 11—12

Show full prerequisite tree

The Particle Model soft
The distinction between physical and chemical change is clearest at the particle level
- Drawing Particle Diagrams hard
  Using the particle model to explain density, compressibility, and anomalous expansion requires fluent reading and drawing of particle diagrams
- Matter Is Made of Particles hard
  KS3 particle model extends US KS2 introduction to matter as particles too small to see
  - Drawing Particle Diagrams hard
    Developing a model of matter as particles too small to see is built on the particle diagram representation
  - Heating & Cooling Changes hard
    Must observe state changes before explaining them with particle model
    - States of Matter Vocabulary hard
      Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
    - Drawing Particle Diagrams hard
      Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
  - Solids, Liquids & Gases hard
    Must understand observable states of matter before modelling them with particles
    - States of Matter Vocabulary hard
      Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
    - Drawing Particle Diagrams hard
      Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
    - Heating & Cooling Changes hard
      Must classify states of matter before understanding changes between states
      - States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
      - Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
    - Grouping Materials hard
      Must group materials by properties before classifying into three states of matter
      - Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
    - Changing Shapes of Solids soft
      Changing shapes of solids provides context for understanding solid properties
      - Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
- Solids, Liquids & Gases hard
  KS3 particle model extends KS2 classification of solids, liquids and gases by observable properties
  - States of Matter Vocabulary hard
    Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
  - Drawing Particle Diagrams hard
    Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
  - Heating & Cooling Changes hard
    Must classify states of matter before understanding changes between states
    - States of Matter Vocabulary hard
      Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
    - Drawing Particle Diagrams hard
      Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
  - Grouping Materials hard
    Must group materials by properties before classifying into three states of matter
    - Describing Material Properties hard
      Must describe properties before using them to group materials
      - States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
      - Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
  - Changing Shapes of Solids soft
    Changing shapes of solids provides context for understanding solid properties
    - Describing Material Properties hard
      Must know material properties before investigating how shapes change
      - States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
      - Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
Conservation of Mass hard
KS3 conservation of mass in reactions extends US KS2 evidence that mass is conserved regardless of change type
- Irreversible Changes hard
  Must understand irreversible changes before proving mass is conserved in all types of change
  - Reversible Changes hard
    Must understand reversible changes before contrasting with irreversible ones
    - Changes & Separation Vocabulary soft
      Describing dissolving and changes of state as reversible requires the vocabulary from the process terms node
    - Dissolving & Solutions hard
      Must understand dissolving before demonstrating it is reversible
      - Changes & Separation Vocabulary hard
        Understanding dissolving and solutions requires 'dissolve', 'solution', 'soluble', 'insoluble' from the process vocabulary node
      - Advanced Material Properties hard
        Must understand solubility as a property before learning dissolving and recovery in detail
        
        Testing Materials for Uses soft
        Within GB sequence, testing advanced properties supports justifying material choices; US teaches material uses earlier without this prerequisite
        
        Material Properties Vocabulary soft
        Giving evidence-based reasons for material uses draws on conductor, insulator, and other property vocabulary
        
        Material Properties Vocabulary hard
        Grouping materials by hardness, solubility, transparency, conductivity, and magnetic response requires all these property terms
        
        Choosing the Right Material hard
        Must understand material suitability before testing advanced properties like conductivity and solubility
        
        Material Properties Vocabulary soft
        Comparing suitability of materials for uses requires property vocabulary to articulate why one material is better than another
        
        Grouping Materials hard
        Must group materials by properties before evaluating suitability for purposes
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
        
        Solids, Liquids & Gases soft
        Understanding states of matter supports testing properties like solubility
        
        States of Matter Vocabulary hard
        Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
        
        Drawing Particle Diagrams hard
        Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
        
        Heating & Cooling Changes hard
        Must classify states of matter before understanding changes between states
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Grouping Materials hard
        Must group materials by properties before classifying into three states of matter
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
        
        Changing Shapes of Solids soft
        Changing shapes of solids provides context for understanding solid properties
        
        Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
      - Evaporation & the Water Cycle soft
        Evaporation knowledge supports understanding recovery of dissolved substances
        
        Changes & Separation Vocabulary hard
        Identifying the role of evaporation and condensation requires knowing these process terms precisely
        
        The Water Cycle soft
        Water cycle connects to curriculum evaporation/condensation topic
        
        Cloud Types hard
        Water cycle requires understanding cloud formation (condensation)
        
        Rain & Puddles hard
        Cloud types build on knowing rain comes from clouds
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
        
        Where water is found on Earth soft
        Water cycle benefits from knowing where water is found on Earth
        
        Shapes of land and water hard
        Must know land and water features before learning where water is found on Earth
        
        Seasonal changes soft
        Seasonal observation supports understanding land and water features
        
        Days, Weeks, Months & Years soft
        Observing and describing seasonal changes requires basic date and time vocabulary (months, seasons, year)
        
        Ordering Events in Time hard
        Understanding days/months/years builds on sequencing events chronologically
        
        Heating & Cooling Changes soft
        Understanding state changes supports knowing water as solid (ice) and liquid
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Heating & Cooling Changes soft
        Water cycle benefits from curriculum states of matter (heating/cooling changes state)
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Temperature & Thermometers soft
        Water cycle evaporation relates to temperature (heat drives evaporation)
        
        Rain & Puddles hard
        Full water cycle builds on basic rain/puddle/evaporation concept
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
        
        Heating & Cooling Changes hard
        Must understand state changes before learning about evaporation/condensation in water cycle
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
    - Heating & Cooling Changes hard
      Must understand state changes before categorising them as reversible
      - States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
      - Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
- Reversible Changes hard
  Must understand reversible changes before investigating conservation of mass during changes
  - Changes & Separation Vocabulary soft
    Describing dissolving and changes of state as reversible requires the vocabulary from the process terms node
  - Dissolving & Solutions hard
    Must understand dissolving before demonstrating it is reversible
    - Changes & Separation Vocabulary hard
      Understanding dissolving and solutions requires 'dissolve', 'solution', 'soluble', 'insoluble' from the process vocabulary node
    - Advanced Material Properties hard
      Must understand solubility as a property before learning dissolving and recovery in detail
      - Testing Materials for Uses soft
        Within GB sequence, testing advanced properties supports justifying material choices; US teaches material uses earlier without this prerequisite
        
        Material Properties Vocabulary soft
        Giving evidence-based reasons for material uses draws on conductor, insulator, and other property vocabulary
      - Material Properties Vocabulary hard
        Grouping materials by hardness, solubility, transparency, conductivity, and magnetic response requires all these property terms
      - Choosing the Right Material hard
        Must understand material suitability before testing advanced properties like conductivity and solubility
        
        Material Properties Vocabulary soft
        Comparing suitability of materials for uses requires property vocabulary to articulate why one material is better than another
        
        Grouping Materials hard
        Must group materials by properties before evaluating suitability for purposes
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
      - Solids, Liquids & Gases soft
        Understanding states of matter supports testing properties like solubility
        
        States of Matter Vocabulary hard
        Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
        
        Drawing Particle Diagrams hard
        Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
        
        Heating & Cooling Changes hard
        Must classify states of matter before understanding changes between states
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Grouping Materials hard
        Must group materials by properties before classifying into three states of matter
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
        
        Changing Shapes of Solids soft
        Changing shapes of solids provides context for understanding solid properties
        
        Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
    - Evaporation & the Water Cycle soft
      Evaporation knowledge supports understanding recovery of dissolved substances
      - Changes & Separation Vocabulary hard
        Identifying the role of evaporation and condensation requires knowing these process terms precisely
      - The Water Cycle soft
        Water cycle connects to curriculum evaporation/condensation topic
        
        Cloud Types hard
        Water cycle requires understanding cloud formation (condensation)
        
        Rain & Puddles hard
        Cloud types build on knowing rain comes from clouds
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
        
        Where water is found on Earth soft
        Water cycle benefits from knowing where water is found on Earth
        
        Shapes of land and water hard
        Must know land and water features before learning where water is found on Earth
        
        Seasonal changes soft
        Seasonal observation supports understanding land and water features
        
        Days, Weeks, Months & Years soft
        Observing and describing seasonal changes requires basic date and time vocabulary (months, seasons, year)
        
        Ordering Events in Time hard
        Understanding days/months/years builds on sequencing events chronologically
        
        Heating & Cooling Changes soft
        Understanding state changes supports knowing water as solid (ice) and liquid
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Heating & Cooling Changes soft
        Water cycle benefits from curriculum states of matter (heating/cooling changes state)
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Temperature & Thermometers soft
        Water cycle evaporation relates to temperature (heat drives evaporation)
        
        Rain & Puddles hard
        Full water cycle builds on basic rain/puddle/evaporation concept
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
      - Heating & Cooling Changes hard
        Must understand state changes before learning about evaporation/condensation in water cycle
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
  - Heating & Cooling Changes hard
    Must understand state changes before categorising them as reversible
    - States of Matter Vocabulary hard
      Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
    - Drawing Particle Diagrams hard
      Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
- Matter Is Made of Particles soft
  Particle model supports understanding why mass is conserved (particles aren't destroyed)
  - Drawing Particle Diagrams hard
    Developing a model of matter as particles too small to see is built on the particle diagram representation
  - Heating & Cooling Changes hard
    Must observe state changes before explaining them with particle model
    - States of Matter Vocabulary hard
      Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
    - Drawing Particle Diagrams hard
      Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
  - Solids, Liquids & Gases hard
    Must understand observable states of matter before modelling them with particles
    - States of Matter Vocabulary hard
      Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
    - Drawing Particle Diagrams hard
      Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
    - Heating & Cooling Changes hard
      Must classify states of matter before understanding changes between states
      - States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
      - Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
    - Grouping Materials hard
      Must group materials by properties before classifying into three states of matter
      - Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
    - Changing Shapes of Solids soft
      Changing shapes of solids provides context for understanding solid properties
      - Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
Irreversible Changes hard
KS3 chemical changes deepens KS2 understanding that burning, rusting and acid reactions form new materials
- Reversible Changes hard
  Must understand reversible changes before contrasting with irreversible ones
  - Changes & Separation Vocabulary soft
    Describing dissolving and changes of state as reversible requires the vocabulary from the process terms node
  - Dissolving & Solutions hard
    Must understand dissolving before demonstrating it is reversible
    - Changes & Separation Vocabulary hard
      Understanding dissolving and solutions requires 'dissolve', 'solution', 'soluble', 'insoluble' from the process vocabulary node
    - Advanced Material Properties hard
      Must understand solubility as a property before learning dissolving and recovery in detail
      - Testing Materials for Uses soft
        Within GB sequence, testing advanced properties supports justifying material choices; US teaches material uses earlier without this prerequisite
        
        Material Properties Vocabulary soft
        Giving evidence-based reasons for material uses draws on conductor, insulator, and other property vocabulary
      - Material Properties Vocabulary hard
        Grouping materials by hardness, solubility, transparency, conductivity, and magnetic response requires all these property terms
      - Choosing the Right Material hard
        Must understand material suitability before testing advanced properties like conductivity and solubility
        
        Material Properties Vocabulary soft
        Comparing suitability of materials for uses requires property vocabulary to articulate why one material is better than another
        
        Grouping Materials hard
        Must group materials by properties before evaluating suitability for purposes
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
      - Solids, Liquids & Gases soft
        Understanding states of matter supports testing properties like solubility
        
        States of Matter Vocabulary hard
        Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
        
        Drawing Particle Diagrams hard
        Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
        
        Heating & Cooling Changes hard
        Must classify states of matter before understanding changes between states
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Grouping Materials hard
        Must group materials by properties before classifying into three states of matter
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
        
        Changing Shapes of Solids soft
        Changing shapes of solids provides context for understanding solid properties
        
        Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
    - Evaporation & the Water Cycle soft
      Evaporation knowledge supports understanding recovery of dissolved substances
      - Changes & Separation Vocabulary hard
        Identifying the role of evaporation and condensation requires knowing these process terms precisely
      - The Water Cycle soft
        Water cycle connects to curriculum evaporation/condensation topic
        
        Cloud Types hard
        Water cycle requires understanding cloud formation (condensation)
        
        Rain & Puddles hard
        Cloud types build on knowing rain comes from clouds
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
        
        Where water is found on Earth soft
        Water cycle benefits from knowing where water is found on Earth
        
        Shapes of land and water hard
        Must know land and water features before learning where water is found on Earth
        
        Seasonal changes soft
        Seasonal observation supports understanding land and water features
        
        Days, Weeks, Months & Years soft
        Observing and describing seasonal changes requires basic date and time vocabulary (months, seasons, year)
        
        Ordering Events in Time hard
        Understanding days/months/years builds on sequencing events chronologically
        
        Heating & Cooling Changes soft
        Understanding state changes supports knowing water as solid (ice) and liquid
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Heating & Cooling Changes soft
        Water cycle benefits from curriculum states of matter (heating/cooling changes state)
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
        
        Temperature & Thermometers soft
        Water cycle evaporation relates to temperature (heat drives evaporation)
        
        Rain & Puddles hard
        Full water cycle builds on basic rain/puddle/evaporation concept
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
      - Heating & Cooling Changes hard
        Must understand state changes before learning about evaporation/condensation in water cycle
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
  - Heating & Cooling Changes hard
    Must understand state changes before categorising them as reversible
    - States of Matter Vocabulary hard
      Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
    - Drawing Particle Diagrams hard
      Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
Reversible Changes hard
KS3 physical vs chemical changes extends KS2 reversible vs irreversible changes
- Changes & Separation Vocabulary soft
  Describing dissolving and changes of state as reversible requires the vocabulary from the process terms node
- Dissolving & Solutions hard
  Must understand dissolving before demonstrating it is reversible
  - Changes & Separation Vocabulary hard
    Understanding dissolving and solutions requires 'dissolve', 'solution', 'soluble', 'insoluble' from the process vocabulary node
  - Advanced Material Properties hard
    Must understand solubility as a property before learning dissolving and recovery in detail
    - Testing Materials for Uses soft
      Within GB sequence, testing advanced properties supports justifying material choices; US teaches material uses earlier without this prerequisite
      - Material Properties Vocabulary soft
        Giving evidence-based reasons for material uses draws on conductor, insulator, and other property vocabulary
    - Material Properties Vocabulary hard
      Grouping materials by hardness, solubility, transparency, conductivity, and magnetic response requires all these property terms
    - Choosing the Right Material hard
      Must understand material suitability before testing advanced properties like conductivity and solubility
      - Material Properties Vocabulary soft
        Comparing suitability of materials for uses requires property vocabulary to articulate why one material is better than another
      - Grouping Materials hard
        Must group materials by properties before evaluating suitability for purposes
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
    - Solids, Liquids & Gases soft
      Understanding states of matter supports testing properties like solubility
      - States of Matter Vocabulary hard
        Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
      - Drawing Particle Diagrams hard
        Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
      - Heating & Cooling Changes hard
        Must classify states of matter before understanding changes between states
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
      - Grouping Materials hard
        Must group materials by properties before classifying into three states of matter
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
      - Changing Shapes of Solids soft
        Changing shapes of solids provides context for understanding solid properties
        
        Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
  - Evaporation & the Water Cycle soft
    Evaporation knowledge supports understanding recovery of dissolved substances
    - Changes & Separation Vocabulary hard
      Identifying the role of evaporation and condensation requires knowing these process terms precisely
    - The Water Cycle soft
      Water cycle connects to curriculum evaporation/condensation topic
      - Cloud Types hard
        Water cycle requires understanding cloud formation (condensation)
        
        Rain & Puddles hard
        Cloud types build on knowing rain comes from clouds
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
      - Where water is found on Earth soft
        Water cycle benefits from knowing where water is found on Earth
        
        Shapes of land and water hard
        Must know land and water features before learning where water is found on Earth
        
        Seasonal changes soft
        Seasonal observation supports understanding land and water features
        
        Days, Weeks, Months & Years soft
        Observing and describing seasonal changes requires basic date and time vocabulary (months, seasons, year)
        
        Ordering Events in Time hard
        Understanding days/months/years builds on sequencing events chronologically
        
        Heating & Cooling Changes soft
        Understanding state changes supports knowing water as solid (ice) and liquid
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
      - Heating & Cooling Changes soft
        Water cycle benefits from curriculum states of matter (heating/cooling changes state)
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
      - Temperature & Thermometers soft
        Water cycle evaporation relates to temperature (heat drives evaporation)
      - Rain & Puddles hard
        Full water cycle builds on basic rain/puddle/evaporation concept
        
        Types of Weather soft
        Rain concept benefits from knowing rain as a weather type
    - Heating & Cooling Changes hard
      Must understand state changes before learning about evaporation/condensation in water cycle
      - States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
      - Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
- Heating & Cooling Changes hard
  Must understand state changes before categorising them as reversible
  - States of Matter Vocabulary hard
    Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
  - Drawing Particle Diagrams hard
    Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
Atoms, Elements & Compounds hard
Chemical changes involve rearrangement of atoms into new substances — atom/compound concepts are required
- The Particle Model hard
  Atoms and molecules are the particles referred to in the particle model — builds directly on it
  - Drawing Particle Diagrams hard
    Using the particle model to explain density, compressibility, and anomalous expansion requires fluent reading and drawing of particle diagrams
  - Matter Is Made of Particles hard
    KS3 particle model extends US KS2 introduction to matter as particles too small to see
    - Drawing Particle Diagrams hard
      Developing a model of matter as particles too small to see is built on the particle diagram representation
    - Heating & Cooling Changes hard
      Must observe state changes before explaining them with particle model
      - States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
      - Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
    - Solids, Liquids & Gases hard
      Must understand observable states of matter before modelling them with particles
      - States of Matter Vocabulary hard
        Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
      - Drawing Particle Diagrams hard
        Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
      - Heating & Cooling Changes hard
        Must classify states of matter before understanding changes between states
        
        States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
        
        Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
      - Grouping Materials hard
        Must group materials by properties before classifying into three states of matter
        
        Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
      - Changing Shapes of Solids soft
        Changing shapes of solids provides context for understanding solid properties
        
        Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
  - Solids, Liquids & Gases hard
    KS3 particle model extends KS2 classification of solids, liquids and gases by observable properties
    - States of Matter Vocabulary hard
      Comparing and grouping materials as solids, liquids, or gases requires the naming vocabulary for the three states
    - Drawing Particle Diagrams hard
      Comparing and grouping solids, liquids, and gases by properties is greatly aided by the particle diagram representation
    - Heating & Cooling Changes hard
      Must classify states of matter before understanding changes between states
      - States of Matter Vocabulary hard
        Describing and measuring changes of state requires solid/liquid/gas vocabulary and the term 'change of state'
      - Drawing Particle Diagrams hard
        Observing and describing change of state requires reading particle diagrams showing how arrangement changes on heating or cooling
    - Grouping Materials hard
      Must group materials by properties before classifying into three states of matter
      - Describing Material Properties hard
        Must describe properties before using them to group materials
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials
    - Changing Shapes of Solids soft
      Changing shapes of solids provides context for understanding solid properties
      - Describing Material Properties hard
        Must know material properties before investigating how shapes change
        
        States of Matter Vocabulary soft
        Describing physical properties of materials uses solid/liquid/gas vocabulary introduced in the states of matter LANGUAGE node
        
        Naming Everyday Materials hard
        Must name materials before describing their properties
        
        Objects vs Materials hard
        Must distinguish objects from materials before naming specific materials

Unlocks1

Types of Chemical Reaction
hardAges 12—13