Review: Particles, Mass and Mixtures
Model matter and compare changes with conserved mass.
Bring the unit skills together
Use these 4 new cases to check your reasoning. Choices are temporary and are not saved to an account, sent to staff or recorded as school grades. Download your current review choices before leaving or reloading.
The download contains your current choices and any checked feedback. Keep the separate transfer-task work in your own document; downloading its instructions does not mark it complete.
Use the skills in a new task
Draw or write four parts for “Particles, Mass and Mixtures”—one pretend example from each lesson. In each part, show what happened, give your answer, and say which clue helped you. If the question gives numbers, show your working too. Finish with one thing the practice case does not tell us. You may say your answers aloud.
Work on paper or in your own document. Explain the choices you made.
- Choose one pretend example from each of the four lessons.
- Name what each example shows.
- If the example gives numbers, show your calculation and unit. Otherwise, say which clue explains your answer.
- Say that the case details are supplied for practice; they are not your own real-life observations.
- Say one thing the example does not tell us, or one change that could give a different answer.
Compare with a model response
Panel 1: Which scientific label fits the specifically described step or feature? Supplied case: Closely packed particles vibrate in place. Result: solid model. Reasoning: The answer is solid model. In the notes, it means “particles stay near fixed relative positions.” 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. Model limitation: only the stated classroom boundary and supplied observations are established; unmeasured real-world performance remains unverified. Panel 2: Supplied case 1: water mass (g)=20; solute mass (g)=5, using the explicitly named quantities. Total mass equals the two supplied material masses. What result follows? Result: 25 g. Reasoning: Substitute the supplied values: (20)+(5) = 25 g. Add masses in grams. Dissolved matter remains present even when invisible. Model limitation: only the stated classroom boundary and supplied observations are established; unmeasured real-world performance remains unverified. Panel 3: Which scientific label fits the specifically described step or feature? Supplied case: Large stones mixed with small sand. Result: sieving. Reasoning: The answer is sieving. In the notes, it means “separates by different particle sizes.” A mixture contains substances that can retain distinguishable properties. A separation method must match those properties. Supplied observations replace any actual mixing or heating. Model limitation: only the stated classroom boundary and supplied observations are established; unmeasured real-world performance remains unverified. Panel 4: Which scientific label fits the specifically described step or feature? Supplied case: Sand and stones mixed. Result: physical mixture. Reasoning: The answer is physical mixture. In the notes, it means “components combine without new substances.” Mixing does not always create a new substance. A chemical reaction changes substances. Appearance alone is incomplete evidence; the supplied record explicitly states whether a new substance forms. Model limitation: only the stated classroom boundary and supplied observations are established; unmeasured real-world performance remains unverified.
A different response can also meet the criteria. Compare the evidence and reasoning, rather than copying the wording.