Standard enthalpy changes

Question 1

What is the standard temperature?

Answer 1

298K

Question 2

What is the standard pressure?

Answer 2

100kPa

Question 3

What is the standard concentration?

Answer 3

1 mol dm⁻³

Question 4

What is a standard state?

Answer 4

The most stable physical state of a substance under standard conditions - e.g. H2O (l)

Question 5

What is standard enthalpy change of combustion?

Answer 5

The enthalpy change that takes place when one mole of substance reacts completely under standard conditions with all reactants and products being in their standard states

Question 6

What is standard enthalpy change of formation?

Answer 6

The enthalpy change that takes place when one mole of a compound is formed from its constituent elements in their standard states under standard conditions

Question 7

What is standard enthalpy change of neutralisation?

Answer 7

The enthalpy change that accompanies the reaction of an acid with a base to form one mole of water under standard conditions with all reactants and products in their standard states.

Question 8

What is the symbol for standard enthalpy change of combustion?

Answer 8

ΔcH°

Question 9

What is the symbol for standard enthalpy change of formation?

Answer 9

ΔfH°

Question 10

What is the symbol for standard enthalpy change of neutralisation?

Answer 10

ΔneutH°