Chapter 1 Retest

Four students create Venn diagrams to compare acids and bases.

Which of these Venn diagrams is NOT correct?

• 
• 
• 
• 

Which of the statements related to the conservation of mass is NOT true?

• In a closed system, the mass of the reactants will equal the mass of the products.

• Matter can be created but not destroyed.

• Matter cannot be created or destroyed.

• The mass of matter in a closed system will not change no matter what type of reaction occurs.

  
  

Photosynthesis is the process by which green plants use carbon dioxide and water to make sugars. The chemical equation for photosynthesis is shown.

How many atoms are involved in the reaction?

• 26

• 30

• 36

• 72

Water striders are a group of insects that are slender and have long legs. Water striders can “walk on water”, catching and eating other insects on the water.

Which statement best explains how water striders can walk on water?

• Water has a high surface tension because the water molecules have high adhesion, so water striders can walk on the water without breaking the attractive forces of the water molecules.

• Water has a high surface tension because the water molecules have high cohesion, so water striders can walk on the water without breaking the attractive forces of the water molecules.

• Water has a high surface tension because the water molecules have high adhesion and cohesion, so water striders can walk on the water without breaking the attractive forces of the water molecules.

• Water has a low surface tension because the water molecules have high cohesion, so water striders can walk on the water without breaking the attractive forces of the water molecules.

Use the image below to help you choose the best answer for questions 4 through 6.

Analyze: Which of the models show elements only?

• 5

• 6

• 5 and 6

• 4 and 5

Use the image below to help you choose the best answer for questions 4 through 6.

Determine: Which models show a homogeneous mixture?

• 6

• 1, 3, 4, and 5

• 1 and 4

• 5 and 6

A pool was tested using a pH testing strip. The key and results are shown below.

What is the current pH value of the pool and what does this tell us?

• The pH level of the pool is at a 3. This means that the pool is currently acidic and needs to be balanced before it is safe to go in.

• The pH level of the pool is at a 3. This means that the pool is currently basic and needs to be balanced before it is safe to go in.

• The pH level of the pool is at a 3. This means that the pool is currently neutral and is perfectly safe to go in as it is neither acidic nor basic.

• The pH level of the pool is at a 5. This means that the pool is currently acidic and needs to be balanced before it is safe to go in.

Identify: Capillary action happens because of what property of water?

• adhesion

• cohesion

• surface tension

• property

Two solutions are mixed and react to produce AgCl. The chemical reaction is shown by the balanced equation.

What happens to the total mass as the reaction takes place?

• The mass increases.

• The mass decreases.

• The mass remains constant.

• The mass first increases and then decreases.

What atoms are involved in this chemical reaction?

• calcium, cobalt, and oxygen

• calcium, carbon, and oxygen

• carbon and oxygen

• calcium, carbon, and cobalt