Calorimetry

Question 1

Equation for heat energy

Answer 1

q=mc delta T

Question 2

Specific heat capacity

Answer 2

Energy required to heat up 1g of a substance by 1 degree

Question 3

Specific heat capacity of water

Answer 3

4.18 JK-1g-1

Question 4

Specific heat capacity of a solution

Answer 4

Presumed to be same as water (4.18)

Question 5

Equation for enthalpy change

Answer 5

Delta H = -q/n

Question 6

Sources of error in flame calorimetry

Answer 6

Heat lost to surroundings (container and air)
Some heat absorbed by calorimeter instead of water
Potential incomplete combustion of water

Question 7

Why do you draw a cooling curve for reactions in solution

Answer 7

It offsets any heat lost during reaction

Question 8

What can you do to minimise heat loss for reactions in solution

Answer 8

Carry out reactions in insulated reaction vessel (polystyrene cup)

Place in beaker for stability

Lid to reduce heat lost by convection

Question 9

What mass do you use for heat energy equation

Answer 9

Equation is q=mc delta T
Use mass of water
When doing solution calculation use both masses combined
Mass (g) will be same as volume (cm3)