Question

The specific heat at constant volume for the monatomic argon is $0.075kcal/kg-K$, whereas its gram molecular specific heat is $C_v=2.98cal/mol/K$. The mass of the argon atom is (Avogadro's number $=6.02\times {10}^{23}$ molecules/mol)

• A. $6.60\times {10}^{-23}g$
• B. $3.30\times {10}^{-23}g$
• C. $2.20\times {10}^{-23}g$
• D. $13.20\times {10}^{-23}g$

Answer 1

Answer: (A)

$6.60\times {10}^{-23}g$

Mass of one mole of argon =$\frac{grammolecularspecificheat}{specificheatatconstantvolume}=\frac{2.98\times {10}^{-3}}{0.075}=0.039733g$

Thus mass of each argon atom=$\frac{0.0397333}{6.02\times {10}^{23}}=6.60\times {10}^{-23}g$