Hydrogen cyanide (HCN)is a poisonous gas that has been used to execute prisoners in the gas chamber.How many moles of HCN are present in a 67.0 L cylinder at 25.0°C that is registering a pressure of 742 mm Hg?

Question

Quizplus · Accepted Answer

To find the moles of HCN in the cylinder, we can use the ideal gas law equation, PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin. First, we need to convert the given values to the appropriate units: pressure in atm (742 mm Hg * 1 atm / 760 mm Hg = 0.976 atm), volume in liters (67.0 L), and temperature in Kelvin (25.0°C + 273.15 = 298.15 K). The ideal gas constant R = 0.0821 L·atm/(mol·K). Plugging these values into the ideal gas law equation and solving for n gives n = PV / RT = (0.976 atm * 67.0 L) / (0.0821 L·atm/(mol·K) * 298.15 K) ≈ 2.67 mol.

Hydrogen Cyanide (HCN)is a Poisonous Gas That Has Been Used