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NeTakaya
4 years ago
7

How much heat is needed to raise the temperature of water with mass of 27.0 g at 20.0°C to 45.0°C?

Chemistry
1 answer:
ohaa [14]4 years ago
7 0

Answer:

2835 J

Explanation:

Take the specific heat capacity of water as 4.2 J/ g°C.

Energy (heat) = mass x specific heat capacity x change in temperature

(E= mcΔT)

E = 27 x 4.2 x (45-20)

E = 2835 J

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Now, from the general law of gases:
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We will just rearrange this equation as follows:
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Then we will substitute n with its equivalent equation mentioned at the beginning:
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mole fraction of hydrogen = 2 x 0.28246 = 0.56492
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