Measuring Energy Content Of Fuel

Question 1

What is the calorimetric experiment?

Answer 1

Heating water by burning liquid fuel

Measuring how much fuel has been burnt and the temperature change of water

Can work out how much energy is supplied by each gram of fuel

Question 2

What do you need to know in the calorimeter experiment if wanting to heat up water using fuel?

Answer 2

Water’s SHC
(Amount of energy needed to raise 1 gram of water to 1C)

SHC of water - 4.2J/g/C

Doing the experiment you can find out how much energy is given off by the fuel to heat up 1gram of water by 1C

Question 3

While doing the experiment, how do you make sure that as much heat as possible goes into heating up the water? And not given off to the environment?

Answer 3

Use a screen to act as a draught excluder or lid to reduce heat loss

Question 4

How do you do the calorimeter experiment?

Answer 4

1. Put fuel into a spirit burner and weigh the burner
2. Measure out your water and pour in a copper CALORIMETER
3. Take the initial temperature of water and put burner underneath the calorimeter and light it
4. When heat from burner made water temperature increase by 20-30C, blow out the spirit burner
5. Make a note on the highest temperature the water reached
6. Reweigh the spirit burner

Question 5

How do you work out the mass of fuel burned?

Answer 5

Before mass of fuel - new mass of fuel

Question 6

How do you work out the amount of energy transferred to the water (from the spirit burner)?

Answer 6

Mass of water x SHC of water x temperature change if water

OR

m x c x change in T

Question 7

How do you work out the energy given out per gram of fuel?

Answer 7

Energy given out per gram =

Energy released (J)
—————-(divided)
Mass of fuel burned (g)