Module 5(Enthalpy and Entropy)

Question 1

First ionisation energy and energy symbol

Answer 1

The change in energy when one mole of electrons is removed from one mole of gaseous atoms to form one mole of +1 ions

positive

Question 2

Second ionisation energy
and energy symbol

Answer 2

The change in energy when one mole of electrons is removed from one mole of gaseous +1 ions to form one mole of +2 ions

positive

Question 3

First electron affinity and energy symbol

Answer 3

The change in energy when one mole of gaseous atoms gain one mole of electrons to form one mole of gaseous 1-ions

negative

Question 4

Second electron affinity and energy symbol

Answer 4

The energy change when one mole of gaseous 1-ions gain one electron to form one mole of gaseous 2- ions

positive

Question 5

Standard enthalpy change of combustion and energy symbol

Answer 5

The enthalpy change when one mole of a substance is completely burned in excess o2, under standard condition

negative

Question 6

Standard enthalpy change of formation and energy symbol

Answer 6

The enthalpy change when one mole of a compound is formed from its element in their standard states, under standard condition

usually negative

Question 7

Standard enthalpy change of neutralisation and energy symbol

Answer 7

The enthalpy change when an acid and an alkali are neutralised forming one mole of water, under standard condition

negative

Question 8

Enthalpy change of atomisation and energy symbol

Answer 8

The enthalpy change when one mole of gaseous atoms are formed from an element in its standard state

positive

Question 9

Lattice enthalpy

Answer 9

The enthalpy change for the formation of one mole of an ionic compound from its gaseous ions under standard condition

negative

Question 10

Enthalpy change of hydration and energy symbol

Answer 10

The enthalpy change when one mole of gaseous ions dissolved in water to form one mole of aqueous ions

negative

Question 11

Enthalpy change of solution and energy symbol

Answer 11

The enthalpy change when one mole of a compound is completely dissolved in water

positive or negative

Question 12

Entropy

Answer 12

A measure of the degree of disorder in a system

Question 13

what is energy symbol for standard enthalpy change of reaction

Answer 13

positive or negative

Question 14

Standard condition

Answer 14

100KPa,298K,1 mol dm-3