7.3 Thermochemical Equations

Front

What is a thermochemical equation?

Back

A thermochemical equation is a balanced chemical equation that includes the enthalpy change (ΔH) associated with the reaction.

Front

What does ΔH represent in a thermochemical equation?

Back

ΔH represents the change in enthalpy, indicating the heat absorbed or released during a chemical reaction.

Front

In the reaction C + O₂ → CO₂ + 60 kJ, what does the +60 kJ signify?

Back

The +60 kJ signifies that 60 kJ of heat is released when 1 mole of CO₂ is formed.

Front

How do you calculate the heat released when forming multiple moles of a product?

Back

Multiply the heat released for 1 mole by the number of moles formed.

Front

If 3 moles of CO₂ are formed in the reaction C + O₂ → CO₂ + 60 kJ, how much heat is released?

Back

180 kJ is released (60 kJ x 3 moles).

Front

What does a positive ΔT indicate about a reaction?

Back

A positive ΔT indicates that heat is being absorbed by the reaction.

Front

What does a negative ΔT indicate about a reaction?

Back

A negative ΔT indicates that heat is being released by the reaction.

Front

What is the specific heat capacity of a substance?

Back

Specific heat capacity is the amount of heat required to raise the temperature of 1 gram of a substance by 1°C.

Front

How do you calculate the final temperature of a mixture of substances?

Back

Use the formula: heat lost by hot substance = heat gained by cold substance.

Front

In the reaction H₂ + ½ O₂ → H₂O, what is the ΔH if 2 moles of O₂ are reacted?

Back

ΔH = -1143.2 kJ when 2 moles of O₂ are reacted.