Question

I can’t solve this anymore cause I don’t know what I am doing wrong.

Answer 1

The mass of H2 is 2.62x10^-3 g.

To calculate the mass of H2 we can use the Ideal Gas formula:

`P\mathrm{}V=n\mathrm{}R\mathrm{}T`

P is the pressure of the gas (atm).

V is the volumen of the gas (L).

n is the number of moles of the gas.

R is the gas constant (0.082 atm.L/mol.K)

T is the temperature of the gas (K).

- First, we need to assume that the pressure is 1 atm, as this information is not given. Then, we have to do the units change so that everything is in the units of the R constant (atm.L/mol.K).

In this case:

P = 1 atm

V= 0.0331 L

T = 308 K

- Second, the number of moles can be calculated from the Ideal Gas formula:m

`\begin{gathered} PV=nRT \\ n=\frac{P\mathrm{}V}{R\mathrm{}T} \\ n=\frac{1atm.0.0331L}{0.082\frac{\text{atm}\mathrm{}L}{\text{mol}\mathrm{}L}.308K} \\ n=1.31x10^(-3)\text{mol} \end{gathered}`

So far, we know that there are 1.31x10^-3 moles of H2.

- Finally, we can calculate the H2 mass from its the molar mass and a mathematical Rule of Three:

`\begin{gathered} 1\text{ mol\_\_\_\_\_\_\_\_\_\_\_ 2g} \\ 1.31x10^(-3)mol\text{\_\_\_\_\_\_ x= }\frac{1.31x10^(-3)mol.2g}{1\text{mol}}_{}_{}_{}_{} \\ x=2.62x10^{-3\text{ }}g \end{gathered}`

So, the mass of H2 is 2.62x10^-3 g.