200g of a solid was uniformly heated by a 0.2 kw heater for sometime. The graph in the figure below shows how the temperature of...

200g of a solid was uniformly heated by a 0.2 kw heater for sometime. The graph in the figure below shows how the temperature of the solid changed with time.

(i) Explain what is happening between OA and AB.
(ii) Calculate the specific heat capacity of the solid.
(iii) Calculate the specific latent heat of fusion k of the solid.

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(i) OA – Temperature of the solid in increasing;
AB- solid is melting;

(ii) Heat supplied = Heat gained
p x t = MC(change in temperature)
200 x 100 = 0.2 x C x 100
20 x 100 = 0.2 x C x (350 – 250)
C= 1000J/Kg/K.

(iii) Heat applied = heat gained; OR
p x t = Mlf; --->where lf is the latent heat of fusion.
200 x 200 = 0.2 x lf;
lf = 200,000J/Kg;

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sharon kalunda answered the question on April 2, 2019 at 07:38

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