Step 1: Convert mass of A to moles. Step 2: Convert moles of A to moles of B. Step 3: Convert moles of B to molecules of B.

Question

In a chemical reaction, exactly 2 mol of substance A react to produce exactly 3 mol of substance B.

2A⟶3B

How many molecules of substance B are produced when 28.0 g of substance A reacts? The molar mass of substance A is 20.5 g/mol.

Answer 1

Hi Ashton,

Step 1: (28 g A)(1molA/20.5 g A) = 1.36 mol A

Step 2: (1.36 molA) (3molB/2molA) = 2.049 mol B

Step 3: (2.049 mol B) (6.023x10^23 molecules / 1 mol B) = 1.234 x 10^24 molecules of B

Hope this helps!