Back to the lesson plan builder
Lesson length30 min45 min60 min
Questions🔀 New questions

Print the plan for yourself; the student sheet prints on its own page after it.

Science lesson plan · 6th grade (Year 7 in England) · 60 minutes

Solutes, solvents and how much will dissolve

Materials and their properties

CCSS NGSS.MS-PS1-2England: KS3 Chemistry: Pure and impure substances

Objective and success criteria

Students will: Solutes, solvents and how much will dissolve.

  • I can answer questions on today's skill on my own, without help.
  • I can explain each step and say why it works.
  • I can check my answer and spot a mistake.

Before and after

Needs first: Dissolving and solutions

Leads to: Choose the right technique to separate a mixture; Concentration in grams per dm³

Materials: A tray of everyday objects, Sorting hoops, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).

Warm-up · 6 min

  • Quick retrieval from earlier learning (Dissolving and solutions). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. Is chalk soluble or insoluble in water? (soluble (dissolves in water) / insoluble (does not dissolve)) → insoluble (does not dissolve)Prompt: Imagine stirring it into a glass of water. Would it disappear from view?
  2. 5 g of salt is dissolved in 250 g of water. What is the mass of the solution, in g? → 255 gPrompt: When something dissolves, does it disappear or is it still there?
  3. In salt water, what is the solvent? (salt water / salt / water / the cup) → waterPrompt: The solvent is the liquid that does the dissolving.

Hook · 6 min

  • Pass round objects made of different materials and ask why each one was chosen.
  • Share the objective: Solutes, solvents and how much will dissolve. Read the success criteria together.

I do: model it · 12 min

  • Work through the example out loud, saying why you do each step, not just what you do.
  • Example: Which word describes this: the clear mixture made when sugar dissolves in water?
  • Step 1: A solution is the mixture of solute and solvent.
  • Step 2: So the answer is: solution
  • Answer: solution
  • Pause after each step and ask a student to say what comes next.

We do: guided practice · 12 min

  • Do these together. Students try each step on whiteboards before you reveal it.
  • Use the hints as prompts rather than giving the answer.
  1. Which word describes this: the clear mixture made when sugar dissolves in water? (saturated solution / insoluble / solute / solution) → solutionPrompt: Solute + solvent → solution.
  2. At 20 °C, 32 g of copper sulfate dissolves in 100 g of water to make a saturated solution. What mass dissolves in 150 g of water at 20 °C, in g? → 48 gPrompt: How many lots of 100 g of water are there?

You do: independent practice · 17 min

  • Students work on the student sheet. Circulate and check the first two answers of every student early.
  • Students who finish: write a question of their own for a partner, with the answer.

The 8 questions are on the student sheet below, with answers in the key.

Exit ticket · 7 min

  • Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
  1. A student adds salt to water until some stays on the bottom however much they stir. What have they made? (a gas / a pure substance / a saturated solution / an insoluble solvent) → a saturated solutionPrompt: No more salt can dissolve.
  2. 10 g of salt is dissolved in 100 g of water. What is the mass of the solution, in g? → 110 gPrompt: Does the salt's mass disappear when it dissolves?

Watch out for

  • Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
  • Remembering facts without the reason: ask "why?" and "what is the evidence?"

Support and stretch

Support

  • Review first: Dissolving and solutions.
  • Use concrete materials: a tray of everyday objects.
  • Give the first step of each question, or a partly worked example to finish.
  • Pair with a confident partner for the guided practice.

Stretch

  • Move on to: Choose the right technique to separate a mixture; Concentration in grams per dm³.
  • Explain a common mistake in writing and how to fix it.
  • Write a word problem that uses today's skill, then solve a partner's.

Homework and more practice

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-6.

Free lesson plan from eurekami.com/lesson-plan-builder

eurekami

Solutes, solvents and how much will dissolve

Name

Date

Score/ 8

  1. Question 1

    At 20 °C, 36 g of salt dissolves in 100 g of water to make a saturated solution. What mass dissolves in 200 g of water at 20 °C, in g?

    Answerg

  2. Question 2

    Which word describes this: sand that sinks to the bottom of water?

    • A. solvent
    • B. insoluble
    • C. solute
    • D. solution

  3. Question 3

    Why does sugar dissolve faster in hot tea than in iced tea?

    • A. Ice stops sugar existing
    • B. Sugar melts in hot tea
    • C. Hot tea has more water in it
    • D. Particles move faster, so solvent particles break the sugar apart more quickly

  4. Question 4

    At 20 °C, 200 g of sugar dissolves in 100 g of water to make a saturated solution. What mass dissolves in 50 g of water at 20 °C, in g?

    Answerg

  5. Question 5

    Which change would let more sugar dissolve in a cup of water?

    • A. using larger sugar lumps
    • B. stirring more slowly
    • C. cooling the water
    • D. heating the water

  6. Question 6

    At 20 °C, 32 g of potassium nitrate dissolves in 100 g of water to make a saturated solution. What mass dissolves in 300 g of water at 20 °C, in g?

    Answerg

  7. Question 7

    Which word describes this: a solution in which no more solute will dissolve?

    • A. saturated solution
    • B. solute
    • C. solvent
    • D. insoluble

  8. Question 8

    At 20 °C, 36 g of salt dissolves in 100 g of water to make a saturated solution. What mass dissolves in 50 g of water at 20 °C, in g?

    Answerg

Free from eurekami.com

for the adult only

Answer key: Solutes, solvents and how much will dissolve

  1. 1. 72 g

  2. 2. B. insoluble

  3. 3. D. Particles move faster, so solvent particles break the sugar apart more quickly

  4. 4. 100 g

  5. 5. D. heating the water

  6. 6. 96 g

  7. 7. A. saturated solution

  8. 8. 18 g