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2 years ago

6

A 155 g sample of an unknown substance was heated from 25°c to 40°c. in the process, the substance absorbed 569 calories of ener

gy. what is the specific heat of the substance?

2 answers:

Umnica [9.8K]2 years ago

6 0

Answer: $0.24cal/g^0C$

Explanation:

The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

$Q=m\times c\times \Delta T$

Q = Heat absorbed= 569 calories

m= mass of substance = 155 g

c = specific heat capacity = ?

Initial temperature = $T_i$ = 25.0°C

Final temperature = $T_f$ = 40.0°C

Change in temperature , $\Delta T=T_f-T_i=(40-25)^0C=15^0C$

Putting in the values, we get:

$569=155\times c\times 15^0C$

$c=0.24cal/g^0C$

The specific heat of the substance is $0.24cal/g^0C$

Tasya [4]2 years ago

5 0

Energy= 2381 joules
heat= Mass(kg) *change in temperature(K) * Cp
2381=0.155*(15)*Cp
Cp=1024 J/kg K

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