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What will be the final temperature of the mixture as a result of mixing 5g ice at 10 ° C with 22 g water at 30 ° C temperature ? The relative heat of ice is 0.5 cal g-l. ° C-1 . |
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Answer» Explanation: Given: 5 g of ICE at −10 o C are mixed with 20g of water at 30 o C. Specific heat of ice is 0.5 and latent heat of water 80calg −1 . To find the final temperature of the mixture Solution: We know, Specific heat of water, s 1
=4.18J/(g ∘ C)=1cal/(g ∘ C) As per the given condition, MASS of ice, m 2
=5g Mass of water, m 1
=20g Temperature of ice, T 2
=−10 ∘ C Temperature of water, T 1
=30 ∘ C specific heat of ice, s 2
=0.5cal/g.°C latent heat of water L=80calg −1 . Let the final temperature be, T Here, Heat lost by 20g water = Heat energy needed to change the temperature of ice from –10°C to 0°C + Latent heat needed to change ice at 0°C into water at 0°C + heat absorbed by water (melted ice) m 1
s 1
(T 1
−T)=m 2
s 2
(0−T 2
)+m 2
L+m 2
s 2
(T−T 2
) ⟹20×1×(30−T)=5×0.5(0−(−10))+5×80+5×1×(T−(0)) ⟹600−20T=25+400+5T ⟹25T=600−400−25 ⟹T=7 ∘ C is the final temperature Mark as brain list |
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