Question

What would happen if the temperature in the lab room was 45.6C on the day of the experiment run? Calculate the theoretical volume of hydrogen gas produced from 0.0150g of aluminum with excess hydrochloride acid at 45.6C and 0.9555 atm to see how the volume is affected by the temperature. Is it what you thought ?

Answer 1

first calculate mole of H₂ produced

Balanced chemical reaction is

2Al + 6HCl 2AlCl₃ + 3H₂

molar mass of Al = 26.98 gm/mole then 0.0150 gm Al = 0.0150/26.98 = 0.000555967 mole

According to reaction 2 mole of Al produce 3 mole of H₂ then 0.000556 mole Al produce H₂ =

0.000556 X 3 /2 = 0.00083 mole

0.00083 mole H₂ porduced

use ideal gas equation to calculate volume of H₂ gas

We know that PV = nRT

V = nRT/P

n = 0.00083 mole,

T = 45.6⁰C = 45.6+273.15 = 318.75K,

P= 0.9555 atm,

R = 0.08205 L atm mol^-1 K^-1 ( R = gas constant)

V = ?

Substitute these value in above equation.

V = 0.00083 X 0.08205 X318.75 / 0.9555 = 0.02272 L = 22.72 ml

22.72 ml H₂ gas produced

According to charle's law volume is directly proportional to tempreture therefore tempreture increases volume also increased tempreture decreases volume decrease.

V T