Question

WILL GIVE BRAINLIEST

Lead melts at 328°c.how much heat is required when 23.0g of solid lead at 297 k condenses to a liquid at 702k

2.04Kj
0.91Kj
0.58Kj
304Kj

Answer 1

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$\bold{Question:-}$


Lead melts at 328°c.how much heat is required when 23.0g of solid lead at 297 k condenses to a liquid at 702k.


$\bold{Answer:-}$


Correct option C) 0.58 KJ

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Answer 2

Lead melts at 328°C. when 23 g of solid lead at 297K condenses to a liquid at 702K.

We have to find the heat is required.

lead melts at 328°C.

so, melting point of lead, T₁ = 328 + 273 = 601K

initial temperature of solid lead, T₂ = 297K

final temperature of lead, T₃ = 702K

from experimental data,

latent head of fusion of lead , Lf = 4.8 kJ/mol

specific heat of solid lead, S = 0.13 J/g/K

specific heat of liquid lead, s = 0.14 J/g/K

heat required = heat required to rise temperature + heat required to melt + heat required to change temperature

= mS∆T + (m/M)Lf + mS∆T'

where M is atomic mass of lead.

= 23g × 0.13 J/g/K × (601 - 297)K + 23g/207g/mol × 4.8 kJ/mol + 23g × 0.14 J/g/K × (702 - 601)K

= 909 J + 0.533kJ + 302 J

= 1.234 kJ + 0.533kJ

= 1.767kJ , it is the nearest value of option (1) 2.04kJ.

hence correct option would be (1) 2.04 kJ.

[ error happens in answer because experimental data is not given in the question. it may choose the different date of specific heat of lead, latent heat of fusion ]