3.2 (enthalpy)

Question 1

standard enthalpy change of reaction

Answer 1

The enthalpy change when the reaction occurs in the molar quantities shown in the chemical equation, under standard conditions

Question 2

standard enthalpy change of formation

Answer 2

the enthalpy change when one more of a compound is formed from it’s elements in their standard states under standard conditions.

Question 3

standard enthalpy change of combustion

Answer 3

the enthalpy change when one mole of a substance us completely burned in oxygen under Standard conditions.

Question 4

standard enthalpy change of neutralisation

Answer 4

the enthalpy change when an acid and an alkali react together under standard conditions to form one mole of water

Question 5

What’s the conservation of energy law?

Answer 5

It states that energy can’t be created or destroyed, only moved from one place to another.

Question 6

What happens in an exothermic reaction?

Answer 6

The enthalpy of the products is smaller than the enthalpy of the reactants.

There is heat loss to the surroundings

There is a negative sign.

Question 7

What is enthalpy?

Answer 7

The thermal energy that is stored in a chemical system.

Question 8

What happens in an endothermic reaction?

Answer 8

The enthalpy of products is greater than the enthalpy of reactants

Question 9

What is average bond enthalpy

Answer 9

The mean needed for one mould of a given type of gaseous bond to undergo homolytic fission