Question

How much boiling water (at 100°C) is needed to melt 2 kg of ice so that the mixture, which is all water, is at 0°C. Given: Sp. heat capacity of water = 4.2 ] g K. Sp. latent heat of ice​

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336 Jg¹.​

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Answer 1

Answer:

Explanation:

Let us start with a basic assumption that the 2kg ice is at  0∘C  and also that the whole system is isolated from the rest of the universe and there is no exchange of energy between the system and the universe. (I know this is over simplification but it helps understand the underlying concept much more clearly. )

Now ice requires heat to melt and form water. This heat is called latent heat of fusion and is  334J/g . This heat is supplied by the 100 degrees boiling water which has heat in the form of sensible heat as it’s relared to change in temperature.

Heat Gained by Ice = Heat Lost by water

2000∗334=M∗4.186∗100  

M=66804.186  

M=1.596kgs  

Thus we require 1.6 Litres of Water at  100∘C