Find the mass of carbonic acid which is formed by the interaction of 80 g of aluminum corbanate and hydrobromic acid.

1. Let’s write down the reaction equation:

Al2 (CO3) 3 + 6HBr = 2AlBr3 + 3H2CO3.

2. Find the amount of aluminum carbonate:

n (Al2 (CO3) 3) = m (Al2 (CO3) 3) / M (Al2 (CO3) 3) = 80 g / 234 g / mol = 0.342 mol.

3. According to the reaction equation, we find the quantity and then the mass of carbonic acid:

3n (H2CO3) = n (Al2 (CO3) 3)

n (H2CO3) = n (Al2 (CO3) 3) / 3 = 0.34 mol / 3 = 0.14 mol.

m (H2CO3) = n (H2CO3) * M (H2CO3) = 0.114 mol * 62 g / mol = 7.07 g.

Answer: m (H2CO3) = 7.07 g.