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3 years ago

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Gallium is a solid metal at room temperature but melts at 29.9 °C. If you hold gallium in your hand, it melts from body heat. Ho

w much heat must 2.5 g of gallium absorb from your hand to raise its temperature from 25.0 °C to 29.9 °C? The specific heat capacity of gallium is 0.372 J/g °C

1 answer:

matrenka [14]3 years ago

7 0

Answer: 4.56 Joules

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 = ?

m= mass of substance = 2.5 g

c = specific heat capacity = $0.372J/g^0C$

Initial temperature = $T_i$ = 25.0°C

Final temperature = $T_f$ = 29.9°C

Change in temperature , $\Delta T=T_f-T_i=(29.9-25.0)^0C=4.90^0C$

Putting in the values, we get:

$Q=2.5\times 0.372\times 4.90^0C$

$Q=4.56J$

The heat absorbed by gallium must be 4.56 Joules

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Putting values in above equation, we get:

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