What is the density (in g/l) of a gas with a molar mass of 70.49 g/mol at 0.874 atm and 389 k?

Given:

Molar mass of gas M = 70.49 g/mol

Pressure P = 0.874 atm

Temperature T = 389 K

To determine:

The density of gas

Explanation:

Density is the ratio of mass to volume

D = m/V

Based on the ideal gas equation:

PV = nRT

where n = number of moles of the gas = mass of gas/molar mass = m/M

R = gas constant = 0.0821 L atm/mol-K

PV = (m/M)RT

m/V = PM/RT = 0.874*70.49/0.0821*389 = 1.93 g/L

Density = 1.93 g/L

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

i would say b

explanation:

but i think i would need more information than that