Required Practical: Specific Heat Capacity

Question 1

What is the aim of the specific heat capacity required practical?

Answer 1

To measure the specific heat capacity (SHC) of a sample of material such as aluminium.

Question 2

What equipment is needed for the SHC experiment with a solid metal block?

Answer 2

• metal block
• immersion heater
• thermometer
• insulation
• joulemeter
• mass balance
• battery pack

Question 3

What is the purpose of the metal block in the SHC experiment?

Answer 3

The block is made of the material being tested (e.g. aluminium) and has holes for the immersion heater and thermometer.

Question 4

What is the purpose of the immersion heater?

Answer 4

To provide heat to the metal block.

Question 5

What is the purpose of the thermometer in this experiment?

Answer 5

To measure the temperature of the metal block accurately.

Question 6

What is the purpose of insulation in the SHC experiment?

Answer 6

To minimise heat loss from the metal block, making measurements more accurate.

Question 7

What is the purpose of the joulemeter?

Answer 7

To measure the amount of energy supplied to the immersion heater.

Question 8

What is the purpose of the mass balance?

Answer 8

To measure the mass of the metal block before starting the experiment.

Question 9

What is the purpose of the battery pack?

Answer 9

To supply power to the immersion heater.

Question 10

Q: Why does the calculated SHC value not match the exact value? | Experimental error occurs because some heat is lost to the surroundings

Answer 10

so the calculated SHC is slightly higher than the true value for 1 kg of the material.

Question 11

Q: What hazards are associated with the SHC practical? | The immersion heater and sample material can cause burns.

Question 12

Q: How can hazards be controlled? | - Do not touch the heater when switched on. - Position away from the edge of the desk. - Allow time to cool before packing away. - Run any burns under cold running water for at least 10 minutes.

Question 13

Q: How can the SHC experiment be extended to investigate different materials? | Repeat the experiment with different solid blocks to compare their SHCs.

Question 14

Q: How does energy transfer from the power supply to the block? | Electrical energy from the power supply does work on the heater

Answer 14

transferring energy electrically to the heater

Question 15

Q: How can the power supplied to the heater be calculated? | Using the formula P = VI

Answer 15

where V is potential difference and I is current.

Question 16

Q: How can the energy transferred at each temperature reading be calculated? | Using the formula E = P × t

Answer 16

where P is power and t is time in seconds since the experiment began.

Question 17

Q: How can a graph be used to determine SHC? | Plot energy transferred to the block versus temperature

Answer 17

find the straight-line portion

Question 18

Q: How can SHC of a liquid be compared to a solid? | Place the heater and thermometer in a known mass of insulated liquid and follow the same procedure as for solids.

Question 19

Q: What is the effect of insulation on measurement accuracy? | Using good insulation (e.g.

Answer 19

polystyrene cup or cotton wool) reduces energy loss

Question 20

Q: What are the full steps to measure the specific heat capacity of a solid block (e.g.

Answer 20

aluminium)? | 1) Measure the mass of the block using a mass balance and record it. 2) Place the block into insulation and insert the immersion heater into the central hole and the thermometer into the smaller hole with a few drops of oil to ensure good contact. 3) Fully insulate the block with cotton wool. 4) Record the initial temperature of the block. 5) Connect the immersion heater to the power supply and joulemeter. 6) Set the potential difference (e.g.