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2 years ago

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750.0g of water that was just boiled (heated to 100.0/c loses 78.45KJ of heat as it cools.What is the final temperature of water

?

1 answer:

Iteru [2.4K]2 years ago

4 0

Mass=m=750g=0.75kg
Q=78.45\times 10^3J=78450J
T_i=100°C
T_f=?
Specific heat capacity=c=4200J/kg°C

According to thermodynamics

$\\ \tt\bull\rightarrowtail Q=mc\Delta T$

$\\ \tt\bull\rightarrowtail Q/mc=\Delta T$

$\\ \tt\bull\rightarrowtail \Delta T=\dfrac{78450}{0.75(4200)}$

$\\ \tt\bull\rightarrowtail \Delta T=24.9°C$

$\\ \tt\bull\rightarrowtail T_i-T_f=24.9$

$\\ \tt\bull\rightarrowtail T_f=100-24.9=76.1°C$

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