5. Air is a good conductor of heat. (1 point)
true
false
6. When you hold a ball above the ground it has kinetic energy. (1 point)
true
false
7. A good refrigerant must have a low boiling point. (1 point)
true
false
Chemistry
To determine the correct answers to these questions, we need to understand the concepts involved. Let's break it down:
5. Is air a good conductor of heat?
To determine the conductivity of a substance, we can consider its physical properties. Air is actually a poor conductor of heat because it is a gas and has low density. Heat is transferred through air mainly by convection, where the air particles move and transfer the thermal energy. Therefore, the correct answer is "false."
6. Does a ball held above the ground have kinetic energy?
Kinetic energy is the energy possessed by an object due to its motion. When you hold a ball above the ground, it is not in motion, so it does not possess kinetic energy. Therefore, the correct answer is "false."
7. Does a good refrigerant have a low boiling point?
Refrigerants are substances used in refrigeration systems to transfer heat. They should have a low boiling point to easily evaporate and absorb heat from the surroundings. This is why refrigerants such as ammonia, R-134a, and R-410A have low boiling points. Therefore, the correct answer is "true."
So, the answers are:
5. False
6. False
7. True