$$803 \text{ kJ} \div 2.00 = 401.5 kJ/$$mol

Question 1

Which of the following statements best describes the First Law of Thermodynamics?

Accepted Answer

Energy can be converted from one form to another, but cannot be created or destroyed.

Question 2

A 75 W light bulb is left on for 1 hour. How much energy, in joules, does it consume? (1 W = 1 J/s)

Accepted Answer

$$75 	imes 3600 = 270,000 J$$

Question 3

Which of the following is an example of an endothermic process?

Accepted Answer

Evaporation of water

Question 4

What is the primary component of natural gas?

Accepted Answer

Methane

Question 5

Which equation correctly expresses the kinetic energy of a moving object?

Accepted Answer

$$E_k = \frac{1}{2}mv^2$

Question 6

Which process is exothermic?

Accepted Answer

Condensation of water vapor

Question 7

When a system absorbs heat from the surroundings, the process is called:

Accepted Answer

Endothermic

Question 8

Which of the following best describes the Second Law of Thermodynamics?

Accepted Answer

The entropy of the universe is increasing, and heat flows from hot to cold objects.

Question 9

Which of the following is a spontaneous process?

Accepted Answer

A ball rolling downhill

Question 10

Combustion of fuels is considered what type of chemical reaction?

Accepted Answer

Exothermic

Question 11

Which of the following factors does NOT increase the rate of a chemical reaction?

Accepted Answer

Decreasing the concentration of reactants

Question 12

Which of the following is true about the energy changes when ice melts?

Accepted Answer

It is an endothermic process because the system absorbs heat.

Question 13

Which of the following is the correct balanced equation for the combustion of methane?

Accepted Answer

$$CH_4(g) + 2O_2(g$$) \rightarrow $$CO_2(g) + 2H_2O(g$$)$$

Question 14

Which of the following best describes potential energy?

Accepted Answer

Energy stored due to position or chemical composition

Question 15

If 2.00 mol of methane releases 803 kJ of heat, how much heat is released per mole?

Accepted Answer

$$803 	ext{ kJ} \div 2.00 = 401.5 kJ/$$mol

Question 16

Which of the following is a correct statement about photosynthesis?

Accepted Answer

It is an endothermic process that stores energy in glucose.

Question 17

Which of the following is the SI unit of energy?

Accepted Answer

Joule (J)

Question 18

Which of the following is a fuel that is a reduced form of matter and releases significant energy when burned?

Accepted Answer

Coal

Question 19

Which of the following is a correct example of energy conversion in a car engine?

Accepted Answer

Chemical energy to kinetic energy

Question 20

Which of the following is true about the entropy of the universe?

Accepted Answer

It is always increasing in spontaneous processes.

Chapter 15: Energy – Introduction to Chemistry Study Notes

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