OL U4 Zone 3

Front

ΔH means:

Back

enthalpy

Front

In the reaction 4Fe + 3O₂ → 2Fe₂O₃, how many moles of Fe₂O₃ are produced?

Back

2 moles

Front

What do thermochemical equations show?

Back

How much heat is absorbed or released during the reaction.

Front

What is the enthalpy change (ΔH) for the reaction given in the image?

Back

-1652 kJ

Front

C + O₂ → CO₂ + 60kJ, what heat is released for the reaction if 3 moles of CO₂ is formed?

Back

180 kJ

Front

What is the definition of enthalpy?

Back

Enthalpy is a measure of the total energy of a thermodynamic system, including internal energy and the energy required to make room for it by displacing its environment.

Front

What is the standard enthalpy of formation?

Back

The standard enthalpy of formation is the change in enthalpy when one mole of a compound is formed from its elements in their standard states.

Front

What is the significance of a negative ΔH value?

Back

A negative ΔH value indicates that a reaction is exothermic, meaning it releases heat to the surroundings.

Front

What is the significance of a positive ΔH value?

Back

A positive ΔH value indicates that a reaction is endothermic, meaning it absorbs heat from the surroundings.

Front

How do you calculate the heat released in a reaction?

Back

Heat released can be calculated using the formula: q = n × ΔH, where n is the number of moles and ΔH is the enthalpy change.