Agas evolved during the fermentation of sugar was collected at 22.5°c and 702 mmhg. after purification its volume was found to be 25.0 l. how many moles of gas were collected?
a) 0.95 mol
b) 1.05 mol
c) 12.5 mol
d) 22.4 mol
e) 724 mol

A) 0.95 mol

Explanation:

We will assume the gas given off in the fermentation is an ideal gas because that allows us to use the ideal gas equation.

PV  = nRT

First let's convert all measurements to units that we can use

P = 702 mmHg * 1 atm/760 mmHg = 0.92368 atm

V = 25.0 L

R = 0.08206 L-atm/mol-K

T = 22.5 °C +273.15 = 295.65 K

PV  = nRT

0.92368 atm * 25.0 L = n * 0.08206 L-atm/mol-K * 295.65 K

                                  n = 0.9518 mol

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.