Definitions (Standard Enthalpy Change)

Enthalpy change (heat liberated or absorbed) when one mole of the pure compound is formed from its elements under standard conditions.

• Standard enthalpy change of neutralisation

• Standard enthalpy change of combustion

• Standard enthalpy change of formation

• Standard enthalpy change of compound

Standard enthalpy change when one mole of the pure substance is completely burnt in excess oxygen under standard conditions

• standard enthalpy change of formation

• standard enthalpy change of burning

• standard enthalpy change of oxidation

• standard enthalpy change of combustion

Standard enthalpy change when one mole of water molecules is formed when an acid reacts with an alkali  under standard conditions

• Standard enthalpy change of formation

• Standard enthalpy change of neutralisation

• Standard enthalpy change of reaction

• Standard enthalpy change of acid base

The heat energy absorbed when one mole of gaseous atoms are formed from its element under standard conditions is _____

• Standard enthalpy change of atomisation for element

• Standard enthalpy change of atomisation for compound

• Standard enthalpy change of reaction

• Standard enthalpy change of gases

The entalpy change is ________

• Standard enthalpy change of atomisation

• Bond energy

• Standard enthalpy chagne of formation

• Covalent bond

This is refer to __________

• Standard enthalpy change of formation

• Standard enthalpy change of atomisation

• Standard enthalpy change of atom

• Standard enthalpy change of compound

Choose the best statement based on this thermochemical equation.

• 234 kJ of heat is absorbed when 2 mole of chlorine is formed.

• 234 kJ of heat is absorbed when 1 mole of gaseous chlorine is formed.

• 234 kJ of heat is absorbed when 1 mole of covalent bond of Cl-Cl is broken.

• +234 kJ/mol is known as standard enthalpy change of atomisation.

The minimum energy required to remove one mole of electrons from one mole of gaseous atoms under standard conditions.

• First ionisation energy

• Second ionisation energy

• First electron affinity

• Second electron affinity

Cl (g) + e^- --> Cl^- (g) ∆H = - 364 kJ/mol

Which of the following statement is true about the thermochemical equation above?

• 364 kJ of heat is released when 1 mol of chlorine receive 1 mol of electron

• 364 kJ of heat is released when 1 mol of chlorine molecules receive 1 mol of electrons

• 728 kJ of heat is released when 2 mol of gaseous chlorine atoms receive 2 mol of electrons

• 728 kJ of heat is released when 1 mol of gaseous chloride ions is formed from gaseous chlorine atoms

Which of the following shows the thermochemical equation for lattice energy of magnesium chloride?

• Mg²⁺ (aq) + 2Cl^- (aq) --> MgCl₂ (s)

• Mg²⁺ (g) + 2Cl^- (g) --> MgCl₂ (s)

• Mg²⁺ (g) + 2Cl^- (g) --> MgCl₂ (aq)

• Mg²⁺ (aq) + 2Cl^- (aq) --> MgCl₂ (aq)