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Heat lost by naphthalene
T = 100-80=20k
H1 = 0.5kg x 2100JK/g/K x 20K = 2100J
Lf = mLf = 0.5kg x 170000J/Kg = 85000J
T = 80 -20 = 60k ,
H2 = 0.5kg x 2100J/Kg/K x 60k = 63000J
Heat lost by aluminium
T = 100 – 20 = 80k
H = 0.4kg x 900J/Kg/K x80k = 28800J
Total heat lost = 169000J + 28800J = 197800J
= 197.8KJ
= 198KJ
sharon kalunda answered the question on April 2, 2019 at 08:23
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