Energetics

Question 1

What is an exothermic reaction?

Answer 1

Gives out energy to the surroundings, usually in the form of heat and usually shown by a rise in temperature of the surroundings

Question 2

What is an endothermic reaction?

Answer 2

Takes in energy from the surroundings, usually in the form of heat and usually shown by a fall in temperature of the surroundings

Question 3

What is the formula for heat energy change?

Answer 3

Q = mass* specific heat capacity* change in temperature

Question 4

How do you calculate the molar enthalpy change?

Answer 4

1) Calculate the heat energy change
2) Find how many moles there are produced in that energy change by using the mass/Mr equation
3) Then you heat energy change/ moles

Question 5

What happens when you break bonds?

Answer 5

It is an endothermic process

Question 6

What happens when you make bonds?

Answer 6

It is an exothermic process

Question 7

How do you calculate enthalpy change from a chemical reaction(bonds being broken or formed)?

Answer 7

Enthalpy change = total energy absorbed to break bonds - total energy released to make bond