Question

According to the following reaction, how many grams of

hydrobromic acid are needed to form 24.7 grams of bromine?

hydrobromic acid (aq) —>hydrogen (g) + bromine (1)

…grams hydrobromic acid

Answer 1

25.1 g

Step-by-step explanation:

Step 1: Write the balanced decomposition reaction

2 HBr(aq) ⇒ H₂(g) + Br₂(l)

Step 2: Calculate the moles corresponding to 24.7 g of Br₂

The molar mass of Br₂ is 159.81 g/mol.

24.7 g × 1 mol/159.81 g = 0.155 mol

Step 3: Calculate the moles of HBr needed to produce 0.155 moles of Br₂

The molar ratio of HBr to Br₂ is 2:1. The moles of HBr needed are 2/1 × 0.155 mol = 0.310 mol.

Step 4: Calculate the mass corresponding to 0.310 moles of HBr

The molar mass of HBr is 80.91 g/mol.

0.310 mol × 80.91 g/mol = 25.1 g