Chem 112 Chapter 9 T/F

When a boulder rolls down a hill, its kinetic energy at the bottom is equal to its change in potential energy (assuming a frictionless surface).

• True

• False

When fuel is burned, the energy of the heat and light produced is equal to the difference in chemical potential energy between the products and reactants of the reaction.

• True

• False

Which of the following are true?

• Energy is conserved, but can be transferred between different forms.

• For exothermic reactions, (delta)H is always positive.

• For endothermic reactions. (delta)H is always positive.

• For endothermic reactions, heat can be treated as a product.

Which of the following are true?

i. If a beaker gets cold during a reaction, it means that the reaction was exothermic.

ii. If a beaker gets hot during a reaction, it means that the reaction was endothermic.

• Only i. is true

• Only ii. is true

• Both i. and ii. are true

• Neither i. nor ii. is true

Which of the following is false?

• The change in enthalpy is the heat transferred to a system under constant pressure and assuming only expansion work.

• The enthalpy of a compound can be determined in absolute terms.

• The enthalpy of formation of a compound is defined relative to its elements in their standard state.

• The enthalpy of formation of an element in its standard state is zero.

Which of the following is true?

• The gas phase of a compound always has higher enthalpy than its liquid phase.

• The solid phase of a compound always has higher enthalpy than its liquid phase.

• The solid phase of a compound always has higher enthalpy than its gas phase.

Which of the following is true?

i. Heating a compound always increases its enthalpy.

ii. Temperature is a measure of motion at the atomic level.

• i. only

• ii. only

• Both i. and ii.

• Neither i. nor ii.

If two objects are put in thermal contact with each other, eventually they will come to a common temperature.

• True

• False

Which of the following is true?

i. The more places that heat can go (the more modes), the higher the compound's heat capacity.

ii. If two compounds absorb the same amount of heat, the one with the larger heat capacity will have a larger change in temperature.

• i. only

• ii. only

• Both i. and ii.

• Neither i. nor ii.

Which of the following is true?

• All gas particles in a three dimensional container have three translational degrees of freedom.

• All gas particles in a three dimensional container have three vibrational degrees of freedom.

• All gas particles in a three dimensional container have three rotational degrees of freedom.