Volume of hydrogen gas = 35.2L
Temperature of hydrogen gas = 25.0°C + 273 = 298 K
Pressure of hydrogen gas = 101.3 kPa = 1 atm
(Conversion factor 1 atm = 101.325 kPa)
Using the Ideal gas law,
PV = nRT
where P, V, n, R and T are pressure, volume, number of moles, universal gas constant and temperature respectively.
n = PV/RT
The number of moles of hydrogen gas,
n = 35.2 L x 1 atm/ 0.0821 L.atm.mol⁻¹1.K⁻¹ x 298 K
n = 1.438 moles
2HCl + Ca → H₂ + CaCl₂
Based on the given balanced equation, 1 mole of H₂ is produced from two moles of HCl.
Since H₂ is 1.438 moles, HCl will be (1.438 x 2) moles or 2.876 moles
Given, Molarity of HCl = 2.3 M
Molarity = moles of solute / liter of the solution
Thus the volume of HCl is,
2.3 M = 2.876 moles / liter of the solution
V = 2.876 moles / 2.3 M
V = 1.25 L
Thus the volume of 2.3 M hydrochloric acid required to produce the given amount gas is 1.25 L.
