What mass of aluminum can be obtained from 16 tons of natural bauxite, the mass fraction of aluminum oxide in which is 75%?

Given: ω (aluminum oxide) = 75%, or 0.75, m (natural bauxite) = 16 tons.
Find: m (aluminum) -?
Decision.
1. Let’s calculate the mass of impurities of aluminum oxide in a sample of natural bauxite:
m (aluminum oxide) = ω (aluminum oxide) • m (natural bauxite) = 0.75 • 16 t = 12 t.
2. Let’s calculate the mass fraction of aluminum in aluminum oxide Al2O3:
Mr (Al2O3) = 2 • Ar (Al) + 3 • Ar (O) = 2 • 27 + 3 • 16 = 102
ω (Al) = 2 • Ar (Al) / Mr (Al2O3) = 2 • 27: 102 = 0.529
3. Calculate the mass of aluminum impurities in the alumina sample:
m (aluminum) = ω (aluminum) • m (aluminum oxide) = 0.529 • 12 t = 6.35 t.
Answer: 6.35 g.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.