Thermochemistry

Front

What is thermochemistry?

Back

Thermochemistry is the study of the heat energy associated with chemical reactions and changes of state.

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-5

Front

Convert 42 kJ into joules.

Back

42000 J

Front

What happens to the temperature of the surroundings during an endothermic reaction?

Back

The surroundings feel cold because heat is absorbed from them.

Front

What is the formula to calculate specific heat capacity?

Back

Specific heat capacity (c) = q / (m × ΔT), where q is heat absorbed, m is mass, and ΔT is the change in temperature.

Tags

NGSS.HS-PS3-1

Front

If a reaction releases heat, what type of reaction is it?

Back

Exothermic reaction.

Tags

NGSS.HS-PS1-4

Front

What is the sign of ΔH for an endothermic reaction?

Back

Positive.

Tags

NGSS.HS-PS1-4

Front

What is the specific heat capacity of a substance if 238 J of heat raises the temperature of 40.7 g of metal from 20.0°C to 32.4°C?

Back

0.472 J/g°C.

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

Front

What is an example of an exothermic reaction?

Back

Combustion of fuels, such as burning wood or gasoline.

Tags

NGSS.HS-PS1-4

Front

What is an example of an endothermic reaction?

Back

Photosynthesis, where plants absorb heat energy.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

Front

What does it mean if a reaction has a negative ΔH?

Back

It indicates that the reaction is exothermic, releasing heat to the surroundings.

Tags

NGSS.HS-PS1-4