Energetics

Question 1

What are standard conditions

Answer 1

25 degrees Celsius
100 kpq
1.0 mol dm3

Question 2

Equations with enthalpy

Answer 2

Energy change = mass of water x specific heat capacity x temp change

Enthalpy change = - energy change / moles

Question 3

Definition of standard enthalpy of combustion

Answer 3

Enthalpy change when 1 mole of a compound is completely burned in oxygen under standard conditions.

Question 4

Definition of standard enthalpy change of formation

Answer 4

Enthalpy change when 1 mole of a compound is formed from its elements in the standard states under standard conditions

Question 5

Definition of enthalpy change for a reaction

Answer 5

Enthalpy change when molar quantities of reactants as stated in the equation react together under standard conditions

Question 6

Definition of standard enthalpy change of neutralisation

Answer 6

Enthalpy change when 1 mole of water is formed from the neutralisation between an acid and an alkali under standard conditions

Question 7

What is the effect of incomplete combustion on calimometry and entgalpy changes

Answer 7

More carbon deposits
Heat loss
Less energy transferred to water
Less negative enthalpy change
Less bonds produced in incomplete so less energy released