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3 years ago

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How much heat energy is required to raise the temperature of 5 kilograms of coal from 20°C to 220°C? A. 314 J B. 6,573 J C. 1,31

4,718 J D. 4,187,000 J

2 answers:

liq [111]3 years ago

8 0

Answer:

C. 1,314,718 J

Explanation:

The heat energy needed to raise the temperature of the coal is given by:

$Q=m C_s \Delta T$

where:

m = 5 kg is the mass of the coal

$C_s = 1314 J/kg ^{\circ}C$ is the specific heat of coal

$\Delta T= 220^{\circ}C-20^{\circ}C=200^{\circ}C$ is the increase in temperature

Substituting into the formula, we find

$Q=(5 kg)(1314 J/kg ^{\circ}C )(200^{\circ}C)=1,314,000 J$

So, the closest option is

C. 1,314,718 J

Vika [28.1K]3 years ago

3 0

Just took the test and the answer is <span>C. 1,314,718.

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