Question

What mass of sulfur gas would be found in a 2.45 liter container at SATP?

Answer 1

`3.21` `"g S"`

Explanation:

We're asked to to find the mass of gaseous sulfur that occupies a volume of `2.45` `"L"` at standard ambient temperature and pressure.

I'll assume for these purposes that the sulfur is present as individual, gaseous atoms, rather than `"S"_8` (which is reasonable considering `"S"_8` is a solid at these conditions).

Standard ambient temperature and pressure (SATP) is defined as

• `298.15` `"K"` (temperature; equal to `25.0^"o""C"`)

• `1` `"atm"` (pressure)

We can use the ideal-gas equation to solve for the number of moles of sulfur, `n`, knowing that the gas constant, `R` is equal to `0.082057("L"•"atm")/("mol"•"K")`:

`PV = nRT`

`n = (PV)/(RT) = ((1cancel("atm"))(2.45cancel("L")))/((0.082057(cancel("L")•cancel("atm"))/("mol"•cancel("K")))(298.15cancel("K")))`

`= color(red)(0.100` `color(red)("mol S"`

Now, let's use the molar mass of sulfur, `32.07` `"g/mol"`, to calculate the number of grams:

`0.100cancel("mol S")((32.07color(white)(l)"g S")/(1cancel("mol S"))) = color(blue)(3.21` `color(blue)("g S"`

Thus, if a `2.45`-`"L"` tank is filled with pure gaseous sulfur at SATP, we can expect the sulfur sample to have a mass of `color(blue)(3.21` `sfcolor(blue)("grams"`.