Heat Transfer and Specific Heat Concepts

Mr. Kenny reviews thermochemistry concepts, focusing on heat transfer, specific heat, and phase changes. He explains endothermic and exothermic processes, specific heat calculations, and the law of conservation of energy. The Doritos lab is used to demonstrate calorimetry and energy conversion. Key topics include heat of vaporization, phase changes, and the role of calorimeters in measuring energy transfer.

What happens to the surroundings when a chemical system releases heat?

• The surroundings absorb the same amount of heat.

• The surroundings remain unaffected.

• The surroundings cool down.

• The surroundings release an equal amount of heat.

Which of the following is true about endothermic reactions?

• The system loses heat.

• The temperature of the system decreases.

• The system gains heat.

• The surroundings gain heat.

What is specific heat?

• The energy needed to change the state of 1 gram of water.

• The energy needed to raise the temperature of 1 liter of water by 1°C.

• The energy needed to cool 1 gram of water by 1°C.

• The energy needed to raise the temperature of 1 gram of water by 1°C.

How does a material with low specific heat feel compared to one with high specific heat?

• Warmer

• Cooler

• The same

• It depends on the material

What is the formula used to calculate specific heat?

• Q = MCT

• Q = CΔT

• Q = MΔT

• Q = MCΔT

What are the units for specific heat in chemistry?

• Joules per gram per degree Celsius

• Calories per gram per degree Celsius

• Joules per liter per degree Celsius

• Calories per liter per degree Celsius

What does a negative Q value indicate in a heat calculation?

• Heat is gained by the system.

• The system is gaining energy.

• Heat is lost from the system.

• The system is at equilibrium.

What is the heat of vaporization?

• The energy required to freeze a liquid.

• The energy used when condensing a gas to a liquid.

• The energy used when boiling a liquid to a gas.

• The energy required to melt a solid.

In the Doritos lab, how is the energy content of the food measured?

• By calculating the mass of the Doritos.

• By measuring the temperature change in water.

• By observing the color change of the Doritos.

• By weighing the Doritos before and after burning.

How does a calorimeter demonstrate the law of conservation of energy?

• By measuring the energy lost to the surroundings.

• By creating energy from food.

• By destroying energy during combustion.

• By converting potential energy to kinetic energy.