Calculate the mass of hydrogen formed when 27 g of

aluminum reacts with excess hydrochloric acid according

to the balanced equation below.

2A1 + 6HCl → 2 AlCl3 + 3 H2

Mass of H₂ formed = 3 g

Explanation:

Given dа ta:

Mass of Al react = 27 g

Mass of H₂ formed = ?

Solution:

Chemical equation:

2Al + 6HCl → 2AlCl₃ + 3H₂

Number of moles of Al:

Number of moles = mass / molar mass

Number of moles = 27 g / 27 g/mol

Number of moles = 1 mol

Now we will compare the moles of Al with hydrogen.

Al : H₂

2 : 3

1 : 3/2*1 = 1.5

Mass of H₂:

Mass = number of moles * molar mass

Mass = 1.5 mol * 2 g/mol

Mass = 3 g