Iculate the amount of gas produced when collected by water d

Iculate the amount of gas produced when collected by water displacement Aluminum reacts with aqueous sodium hydroxide to produce hydrogen gas: 2A1(s) + 2NaOH(aq) + 6H202NaAI(011)4(aq) + 3112(g) In one experiment, a sample of Al reacts and the gas produced is collected by water displacement. The gas sample has a temperature of 21.00 oC, a volume of 656.0 mL, and a pressure of 751.0 mm Hg. Calculate the amount (in moles) of hydrogen gas produced in the reaction. The vapor pressure of water is 18.65 mm Hg at 21.00 C. mol

Solution

Use ideal gas equation to calculate mole of H₂ gas

PV = nRT             where, P = atm pressure= 751 - 18.65 = 732.35 mm Hg = 0.9636 atm,

V = volume in Liter = 656 ml = 0.656 L

n = number of mole = ?

R = 0.08205L atm mol^-1 K^-1 =Proportionality constant = gas constant,

T = Temperature in K = 21⁰C = 273.15+ 21 = 294.15 K

We can write ideal gas equation

n = PV/RT

Substitute the value

n = (0.9636X 0.656)/(0.08205 X 294.15) = 0.025393 mole

0.025393 mole of H₂ gas produced.