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Roman55 [17]
2 years ago
7

PLEASE HELP WITH THESE TWO QUESTIONS

Chemistry
1 answer:
adelina 88 [10]2 years ago
3 0

1. Q=112.8 kJ

2. Q=5.01 kJ

<h3>Further explanation</h3>

The heat required for phase change :

  • melting/freezing :

Q = mLf

Lf=latent heat of fusion

  • vaporization/condensation

Q = mLv

Lv=latent heat of vaporization

1.

m=50 g=0.05 kg

Lv (water) = 2256 kJ/kg

\tt Q=0.05\times 2256=112.8~kJ

2.

m=15 g=0.015 kg

Lf for water = 334 kj/kg

\tt Q=0.015\times 334=5.01~kJ

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