14.A 4.25 gram sample of an unknown gas is found to occupy a volume of 1.70 L at a pressure of 883 mm Hg and a temperature of 58 °C. The molar mass of the unknown gas is g/mol.

58.5g/mol

Explanation:

Given parameters:

Mass of gas  = 4.25g

Volume  = 1.7L

Pressure  = 883mmHg

                760mmHg  = 1 atm

                883mmHg  =   = 1.16atm

Temperature  = 58°C  = 58 + 273  = 331K

Unknown:

Molar mass of sample  = ?

Solution:

To solve this problem, we use the ideal gas equation to find the number of moles;

            PV  = nRT

 P is the pressure

V is the volume

n is the number of moles

R is the gas constant  = 0.082atmdm³mol⁻¹K⁻¹

 T is the temperature

           n  =   =   = 0.07mole

 Since;

            mass  = number of moles x molar mass

            4.25  = 0.07 x molar mass

 Molar mass  = 58.5g/mol

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.