Q1-4. These questions are about sugar water:

 1. When sugar dissolves in warm water, the water is called..

• A. a solute.
• B. a solvent.
• C. a dissolvant.
• D. a dissolute.

2. Sugar dissolves in water easily. This process is..

• A. a chemical change because atoms have been rearranged in a reaction.
• B. a physical change because atoms have been rearranged in a reaction.
• C. a chemical change because NO atoms have been rearranged in a reaction.
• D. a physical change because NO atoms have been rearranged in a reaction.

3. The sugar can be recovered from the water by..

• A. filtering the water.
• B. chromatography.
• C. evaporating the water.
• D. diffusion.

4. Which of these sentences best describes if sugar water is a pure or impure substance?

• A. Pure substance as no other chemicals have been added to the salt water.
• B. Pure substance as all the molecules are the same.
• C. Impure substance as there are several different elements in the sugar water.
• D. Impure substance as there are 2 types of molecules present.

5. Some water in a container used for camping is found to have some sand and other dirt particles in it. What is the simplest method to remove these insoluble particles?

• A. filtering the water.
• B. chromatography.
• C. evaporating the water.
• D. diffusion.

6-8. Some red food colouring is added to a beaker containing hot water. The red colour slowly spreads throughout the water as shown here:

6. What is the name given to this process?

• A. Dispersion.
• B. Diffraction.
• C. Distillation.
• D. Diffusion.

7. How does this process happen?

• A. The particles spread from a small region of low concentration to a larger region of high concentration.
• B. The particles spread from a small region of high concentration to a larger region of low concentration.
• C. The particles spread from a large region of high concentration to a smaller region of low concentration.
• D. The particles spread from a large region of low concentration to a smaller region of high concentration.

8. Complete the following sentence:

If the water is cooler, the red colour will spread ? faster slower at the same rate .

9-10. The image shows some inks separating out as water spreads upwards through some filter paper:

Key:

• 1 = water
• 2 = filter paper
• 3 = black ink dot
• 4 = coloured ink dots
• 5 = water 'front' moving upwards
• 6 = pencil 'start' line

9. What is the name given to this process of separating chemicals?

• A. Filtering.
• B. Chromatography.
• C. Distillation.
• D. Diffusion.

10. Why is pencil used as the bottom line?

• A. It makes it easier to see.
• B. The graphite markings from the pencil are not soluble in water.
• C. The graphite markings from the pencil diffuse easily.
• D. The graphite markings from the pencil are made of several ink colours.