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Calculate the internal energy (in J) of 86 mg of helium at a temperature of 0°C.

User Danyhow
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1 Answer

2 votes

Answer:

The internal energy is 73.20 J.

Step-by-step explanation:

Given that,

Weight of helium = 86 mg

Temperature = 0°C

We need to calculate the internal energy

Using formula of internal energy


U =nc_(v)T

Where,
c_(v) = specific heat at constant volume

He is mono atomic.

So, The value of
c_(v)= (3)/(2)R

now, 1 mole of Helium = 4 g helium

n =number of mole of the 86 mg of helium


n = (86*10^(-3))/(4)


n =2.15*10^(-2)\ mole

T = 0°C=273 K

Put the value into the formula


U = 2.15*10^(-2)*(3)/(2)*8.314*273


U = 73.20\ J

Hence, The internal energy is 73.20 J.

User Boyan Bozhidarov
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