Energy and Thermodynamics Quiz

What is energy?

• The ability to create mass

• The ability to do work or produce heat

• A measure of temperature

• The mass of an object

Which of these is a form of kinetic energy?

• Stored water in a dam

• Moving water from a dam

• A car at rest

• Electrical potential

What is the First Law of Thermodynamics?

• Energy cannot be created or destroyed, only transformed

• Energy is always lost in any conversion

• Heat is the only form of energy

• Potential energy is higher than kinetic energy

In a closed system, if qq (heat) is positive and ww (work) is positive, what happens to the system's internal energy (ΔE)?

• It decreases

• It increases

• It remains the same

• It fluctuates

If energy flows from the surroundings into a system, the reaction is:

• Exothermic

• Endothermic

• Neutral

• Kinetic

Which of the following factors affects a system's internal energy?

• Only temperature

• Only chemical identity

• Temperature, chemical identity, and pressure

• Only pressure

Define enthalpy (H):

• The heat content of a system at constant volume

• The heat content of a system at constant pressure

• The energy needed to change temperature

• Energy due to motion

What is the standard enthalpy change of formation (ΔH_f°) for an element in its standard state?

• A positive value

• A negative value

• Zero

• Depends on the temperature

In an exothermic reaction, what is the sign of ΔH?

• Positive

• Negative

• Neutral

• Undefined

According to Hess's Law, the enthalpy change for a reaction depends on:

• The path taken by the reaction

• The initial and final states only

• The speed of the reaction

• The amount of product only