Use a particle model

Supplied materials

• All measurements and observations below are supplied classroom examples. They are not data from actual learners or a claim about a particular real site.
• Paper, drawing space or a browser document.
• Reference card A: particles stay near fixed relative positions. Reference card B: nearby particles rearrange and flow.
• Assessment case 1: Which scientific label fits the specifically described step or feature? Supplied case: Closely packed particles vibrate in place.
• Assessment case 2: Which scientific label fits the specifically described step or feature? Supplied case: Close particles slide past one another.
• Assessment case 3: Which scientific label fits the specifically described step or feature? Supplied case: Widely spaced particles fill the box.
• Assessment case 4: Which scientific label fits the specifically described step or feature? Supplied case: Red circles do not show actual atom color.
• Assessment case 5: Which scientific label fits the specifically described step or feature? Supplied case: Gas particles spread across container.
• Assessment case 6: Which scientific label fits the specifically described step or feature? Supplied case: Drawn circles are much larger than real particles.

Learn the idea

Matter is made of particles too small to see individually in this model. Particle diagrams represent arrangement and motion, not actual colors or enlarged solid balls. Gas particles still have mass.

Solid model means particles stay near fixed relative positions. Liquid model means nearby particles rearrange and flow. Gas model means particles spread through available space. Model limit means drawn particle size and color are representations.

For solid model, look for the clue “particles stay near fixed relative positions.” For liquid model, look for “nearby particles rearrange and flow.” More than one process can happen in a real situation. Answer about the one described in this question.

1. Read or listen to the four science words and what each means. Say how the first two differ.
2. Choose two of the short cases. Point to the clue that helps you choose a science word for each one. You may draw or say your answer.
3. Answer each practice question. Say which clue helped you, then check the explanation.
4. Use the extra task to make two examples that show different science words. Draw or say what makes each one fit.

Check your reasoning

Your answer is temporary and is not saved to an account. Download your current answer before leaving or reloading. Written work on paper or in another app stays in your own file.

Take it further

Create one new case showing solid model and one showing liquid model. Expected: the first explicitly shows “particles stay near fixed relative positions”; the second explicitly shows “nearby particles rearrange and flow.” Explain the distinction by drawing, speaking or writing. A label without a matching feature is incomplete.

Nothing here is saved to an account or sent to a teacher. The answer download includes your current choice and any checked feedback. It does not include choices from the separate More practice section. Download that section separately.