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3 years ago

6

How much heat, in joules and in calories, must be added to a 75.0Â–g iron block with a specific heat of 0.449 j/g Â°c to increas

e its temperature from 25 Â°c to its melting temperature of 1535 Â°c?

1 answer:

pav-90 [236]3 years ago

4 0

Note that
1 cal = 4.184 J

Given:
m = 75.0 g, the mass of the iron block
c = 0.449 J/(g-°C), the specific heat of iron
Tm = 1535 °C, melting temperature
T0 = 25 °C, initial temperature.

Sensible heat required to raise the temperature of the iron is given by
Q = mc(Tm - T0)
= (75 g)*(0.449 J/(g-°C))*(1535 - 25 °C)
= 50849.25 J = 50.849 kJ

Q = (50849.25 J)*( 1 cal/4.184 J)
= 12153.3 cal

Answer:
50849.3 J or 12153.3 cal

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