Here are the answers to your questions:
Question 19: What happens to the volume of a gas when the temperature is increased?
- c The volume is increased. (This is based on Charles's Law, which states that the volume of a gas is directly proportional to its temperature when pressure is constant.)
Question 20: Which of the following will increase the rate at which a solute dissolves? (Select all that apply.)
- a increasing temperature
- d stirring
- e increasing surface area
(Decreasing temperature and decreasing surface area would decrease the rate at which a solute dissolves.)
Question 21: Match the pH to its description.
- pH above 7: a. basic
- pH below 7: b. acidic
- pH of 7: c. neutral
These descriptions reflect the properties of acids, bases, and neutral solutions according to the pH scale.