Thermal Chemistry Review

ΔH value in an endothermic reaction is a positive number.

• True
• False

A catalyst works by

• changing the order of the reaction
• increasing the temperature
• lowering the activation energy
• making the activated complex

What type of reaction is shown in the reaction pathway?

• endothermic reaction
• exothermic reaction

As 120 g of hot milk cools in a mug, it transfers 20, 000 J of heat to the environment. What is the temperature change of the milk? The specific heat of milk is 2.6 J/g·°C. (Q=mcΔT)

• 64 °C
• 1.56 °C
• 640 °C
• cannot be determined

If 100 g of aluminum at 145ºC gains 6,800 J of heat, what is the final temperature (T_final) of the aluminum? Aluminum has a specific heat of 0.897 J/gºC. (Q=mcΔT)

• -69°C
• 0.52°C
• 221°C

How much heat does an aluminum block absorb if 10.00 grams ae heated from 25.0^oC to 50.0^oC? the specific heat of aluminum is 0.900J/g^oC

• 450
• -450
• 225
• -225

C+ O₂ --> CO₂ + 60kJ, what is the value for ΔH for the reaction?

• +60
• -60
• there is no way to know

Endothermic reactions feel

• warm
• cold

The specific heat of platinum is 0.133 J/g°C. How much heat(Q) is absorbed when a 10 g piece of platinum warms from 100°C to 150°C?

• 66.5 J

• 665 J

• 0.0266 J

• 0.665 J

How many Joules of energy are required to change 10 gram of water from 20 C to 90 C?

• 1476 J
• 2926 J
• 210,050 J
• 1,404,500 J