Enthalpy changes

Question 1

How is △H⦵ pronounced?

Answer 1

Delta H standard

Question 2

What is the definition of the standard molar enthalpy of formation?

Answer 2

The standard molar enthalpy of formation is the enthalpy change when one mole of substance is formed from its constituent elements under standard conditions, all reactions and products being in their standard states

Question 3

What is the enthalpy of formation of CH4 (g)?

Answer 3

C (s) + 2H2 (g) ⇒ CH4

Question 4

What is the definition of the standard molar enthalpy of combustion?

Answer 4

The standard molar enthalpy of combustion is the enthalpy change when one mole of substance is completely burnt in oxygen under standard conditions, all reactions and products being in their standard conditions

Question 5

What is the enthalpy of combustion of CH4 (g)?

Answer 5

CH4 (g) + 2O2 (g) ⇒ CO2 (g) + 2H2O (l)

Question 6

What is the definition of the standard molar enthalpy of neutralisation?

Answer 6

The standard molar enthalpy of neutralisation, is the enthalpy change when one mole of water is formed by reacting an acid and alkali under standard conditions

Question 7

What is the enthalpy of neutralisation of HCl (aq) + NaOH (aq)?

Answer 7

HCl (aq) + NaOH (aq) ⇒ NaOH (aq) + H2O (l)