What mass of charcoal with a mass fraction of carbon 90% is required for the complete

What mass of charcoal with a mass fraction of carbon 90% is required for the complete reduction of iron oxide 3 weighing 320 g (CO is formed)?

1. Let’s write down the reaction equation:

Fe2O3 + 3C = 2Fe + 3CO.

2. Find the amount of iron oxide:

n (Fe2O3) = m (Fe2O3) / M (Fe2O3) = 320g / 160 g / mol = 2 mol.

3. Using the reaction equation, we find the amount of carbon, and then its mass:

n (C) = n (Fe2O3) * 3 = 2 mol * 3 = 6 mol.

m (C) = n (C) * M (C) = 6 mol * 12 g / mol = 72 g.

4. Find the mass of charcoal:

m (coal) = m (C) * 100% / ω (C) = 72 g * 100% / 90% = 80 g.

Answer: m (coal) = 80 g.