What gets through the filter? — questions

1. Describe / Explain

Ordinary filter paper retains sand while salt solution passes through. Identify the residue and explain why it has that name.

Circle one answer.

• Sand left on the paper
• Water collected below
• Salt dissolved in the receiver
• All the starting mixture

Explain what residue means here and why the sand is the residue.

Nudge (only if you are stuck): What stayed behind after liquid passed through the paper?

2. Describe

Sand and salt solution enter a filter. Fill the gaps to describe the filtrate, including both components it contains.

Nudge (only if you are stuck): What must liquid do before it's called filtrate? Did the dissolved salt stay on the paper?

3. Describe / Explain

Water and insoluble chalk grains are filtered. The grains are large enough for the paper to retain. Identify where the chalk ends up and explain why.

Circle one answer.

• Dissolved in the water
• On the paper as residue
• In the receiver as filtrate
• Changed into water

Explain why chalk is found there.

Nudge (only if you are stuck): Does ‘residue’ name a particular substance, or a role in the process?

4. Describe / Explain

In this written case, copper(II) sulfate is fully dissolved in water. Insoluble chalk grains are also present, and ordinary paper retains them. Describe the filtrate. Name its components and explain why they're there.

Nudge (only if you are stuck): Which material stays as grains? Which substance passes with the water because it's dissolved?

5. Explain

Sand and salt solution enter ordinary paper that retains the sand. Complete the account of all components and name the separation achieved.

The undissolved material retained is …

The two components passing together are …

Filtration separates … from …, but does not separate … from …

Nudge (only if you are stuck): Follow sand, water and dissolved salt one at a time. Which two still share a container?

6. Identify / Explain

During filtration, liquid A waits above the paper. Grains B stay on it. Liquid C has crossed into the receiver. Match each label to its role.

Write the number of the matching option.

1. Feed liquid still waiting to pass
2. Filtration residue
3. Collected filtrate

• A: ______
• B: ______
• C: ______

Why is it premature to call A the collected filtrate?

Nudge (only if you are stuck): Which material has actually passed through the filter? Is position alone enough?

7. Predict / Explain

A pupil filters fully dissolved sodium chloride solution through intact ordinary paper. They expect to collect salt on the paper. Predict the outcome and explain whether the plan works.

Circle one answer.

• Salt stays on the paper and pure water passes.
• Salt solution passes through; salt is not recovered on the paper.
• Water stays on the paper and salt passes alone.
• Filtering destroys the dissolved salt.

Explain whether the plan achieves its goal, using the state of the salt.

Nudge (only if you are stuck): Are there undissolved salt grains for this paper to catch?

8. Suggest / Explain

Liquid rises above the paper rim and flows between the paper and its supported funnel. Choose changes that would stop this bypass. Explain why reaching the receiver doesn't prove successful filtration.

Tick every correct statement.

• Pour smaller portions more slowly.
• Keep the liquid below the rim of correctly seated intact paper.
• Pour faster so the liquid rises further.
• Assume clear collected liquid must be correctly filtered.

Explain why the observed route prevents claiming that the liquid was correctly filtered.

Nudge (only if you are stuck): Which route avoids the paper? What changes would make liquid cross it instead?