Unit 4 Test: Matter and Chemical Changes

• Both are compounds made of molecules.

• Both are elements made of atoms.

• Water is an element, and carbon dioxide is a compound.

• Carbon dioxide is an element, and water is a compound.

• 6

• 12

• 18

• 24

Which of the following is a chemical change?

• Melting ice

• Dissolving sugar in water

• Burning wood

• Breaking a glass

Emma is making lemonade by adding sugar to water. Describe what happens to the concentration of the lemonade when more sugar is added without changing the volume of the water.

• The concentration decreases.

• The concentration remains the same.

• The concentration increases.

• The solution becomes saturated.

Priya is making a cup of tea and wants to dissolve sugar quickly. Which factor will increase the rate of dissolution of the sugar in water?

• Decreasing the temperature

• Decreasing the surface area of the sugar

• Stirring the tea

• Using a larger cup

• It is made of two different types of atoms.

• It is a pure substance.

• It cannot be broken down into simpler substances.

• It is found on the periodic table.

• 2

• 4

• 6

• 8

A student observes a rusting nail. Which evidence supports that a chemical change has occurred?

• The nail changes shape.

• The nail becomes warmer.

• The nail changes color.

• The nail breaks into pieces.

If a solution is diluted by adding more solvent, what happens to the concentration of the solute?

• It increases.

• It decreases.

• It remains the same.

• It becomes saturated.

Charlotte is making a cup of tea and wants to dissolve sugar in it faster. Which method should she use?

• Use cold water and leave it undisturbed.

• Use hot water and stir the solution.

• Use cold water and stir the solution.

• Use hot water and leave it undisturbed.