Question

Solve the question What does cc stand for and in -
9.7 * 10^17 atoms of iron weigh as much as 1 cc of H2 at S.T.P. What is the atomic mass of iron?

Answer 1

Answer:

The atomic mass of iron is 55.49 g/mol.

Explanation:

1 cc of $H_2=1cm^3=0.001 L$  

This is the volume of the hydrogen gas at STP.

At STP, Pressure,P = 1 atm

At STP, Temperature,T = 273 K

$PV=nRT$

$1 atm\times 0.001 L=n\times 0.0820 L atm/ mol K\times 273 K$

$n = 4.4670\times 10^{-5} mol$

Mass of $4.4670\times 10^{-5} mol$ of Hydrogen gas = :

$2 g/mol\times 4.4670\times 10^{-5} mol=8.934\times 10^{-5} g$

$9.7\times 10^{17}$ atoms of iron weigh as much as 1 cc of H2 at S.T.P.

Mass of $9.7\times 10^{17}$ atoms of iron =$8.934\times 10^{-5} g$

Moles of iron =$\frac{9.7\times 10^{17}}{6.022\times 10^{23} mol^{-1}}=1.6107\times 10^{-6} mol$

Atomic mass of iron: $\frac{\text{Mass of given atoms}}{Moles}$

:$\frac{8.934\times 10^{-5} g}{1.6107\times 10^{-6} mol}=55.49 g/mol$

The atomic mass of iron is 55.49 g/mol.

Answer 2

Answer:

0.00009

Explanation:

We know for gases at STP - 1mol of gas has a volume of 22.4L or 22,400cc (cm cube)For H2. 2.016g of H2 at STP = 22,400ccMass of 1 cc of H2 = 2.016 /22400 = 0.00009g We know is that 1 mol of anything contains 6.022*10^23 molecules or atoms for monoatomic elements. So, from the question: 9.7*10^17 atoms of Fe has mass = 0.00009g