## Examples

- Calculate the amount of heat needed to increase the temperature of 250g of water from 20
^{o}C to 56^{o}C.q = m x C

_{g}x (T_{f}- T_{i})

m = 250g

C_{g}= 4.18 J^{o}C^{-1}g^{-1}(from table above)

T_{f}= 56^{o}C

T_{i}= 20^{o}Cq = 250 x 4.18 x (56 - 20)

q = 250 x 4.18 x 36

q = 37 620 J = 38 kJ - Calculate the specific heat capacity of copper given that 204.75 J of energy raises the temperature of 15g of copper from 25
^{o}to 60^{o}.q = m x C

_{g}x (T_{f}- T_{i})

q = 204.75 J

m = 15g

T_{i}= 25^{o}C

T_{f}= 60^{o}C204.75 = 15 x C

_{g}x (60 - 25)

204.75 = 15 x C_{g}x 35

204.75 = 525 x C_{g}

C_{g}= 204.75 ÷ 204.75 = 0.39 J^{o}C^{-1}g^{-1} - 216 J of energy is required to raise the temperature of aluminium from 15
^{o}to 35^{o}C. Calculate the mass of aluminium.

(Specific Heat Capacity of aluminium is 0.90 J^{o}C^{-1}g^{-1}).q = m x C

_{g}x (T_{f}- T_{i})

q = 216 J

C_{g}= 0.90 J^{o}C^{-1}g^{-1}

T_{i}= 15^{o}C

T_{f}= 35^{o}C216 = m x 0.90 x (35 - 15)

216 = m x 0.90 x 20

216 = m x 18

m = 216 ÷ 18 = 12g - The initial temperature of 150g of ethanol was 22
^{o}C. What will be the final temperature of the ethanol if 3240 J was needed to raise the temperature of the ethanol?

(Specific heat capacity of ethanol is 2.44 J^{o}C^{-1}g^{-1}).q = m x C

_{g}x (T_{f}- T_{i})

q = 3240 J

m = 150g

C_{g}= 2.44 J^{o}C^{-1}g^{-1}

T_{i}= 22^{o}C3240 = 150 x 2.44 x (T

_{f}- 22)

3240 = 366 (T_{f}- 22)

8.85 = T_{f}- 22

T_{f}= 30.9^{o}C

thank you so much for this it really helped

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