Question

The equation is c= Q/mDeltat

Please, can you give me you feedback on the following steps? In order to investigate how salt concentration will affect the specific heat capacity elaborated the following experiment. I measured the amount of water and I record the initial temperature.Itake an amount x of salt and blend it in the water. I heat the water for 2 minutes and then I measure the final temperature. I do it for the water with salt and without salt. Then I repeat the steps 3 types with 2 different amounts of salt 1. Should I have more trials? Is my methodology good? I will use the following equation 2. Can I say that the energy provided by the kettle is equal to the Oof the equation above? 3. After calculating the specific heat. Now I have all the data. How can I calculate the uncertainty?

Answer 1

I would suggest following methodology:

1.Take a calorimeter with known specific heat and insulate it to prevent heat losses

2. Pour the liquid for you want to measure specific heat in Calorimeter.

3.Supply heat to the liquid by using a heating coil. You can connect an energy meter to measure the heat supplied to Calorimeter plus water

4.Dip a thermometer to measure rise in temperature of liquid

5. The energy supplied by heating element = H (+/-) delta H Joules (say)

6. H = Heat gained by Calorimeter + Heat gained by Liquid

= [Maas of calorimeter x Sp. heat of Calorimeter + Mass of Liquid X sp heat of liquid] (diif in temperature)

or   $C_{l} = [H - M_{Cal}C_{Cal}\Delta T]/ [M_{l}\Delta T]$

I would suggest measurements to be repeated 6 times and average can be worked out.

The main source of experimental error is from measurement of temperature.