Carbon (4) -oxide obtained by burning coal with a mass of 20 g, in which the mass fraction of carbon is 94%, was passed through an excess of barium hydroxide solution. determine the mass of the sediment formed.
Carbon combustion reaction equation:
C + O2 = CO2
m (C) = mcoal (C) * wcoal (C) / 100 = 20 * 94/100 = 18.8 (g).
The amount of carbon substance:
v (C) = m (C) / M (C) = 18.8 / 12 = 1.57 (mol).
According to the reaction equation, from 1 mol of C, 1 mol of CO2 is formed,
therefore v (C) = v (CO2) = 1.57 (mol).
The reaction equation for the formation of barium carbonate:
Ba (OH) 2 + CO2 = BaCO3 + H2O
According to the reaction equation, from 1 mol of CO2, 1 mol of BaCO3 is formed,
therefore v (CO2) = v (BaCO3) = 1.57 (mol).
m (BaCO3) = v (BaCO3) * M (BaCO3) = 1.57 * 197 = 309 (g).
Thus, the mass of barium carbonate sediment is 309 g.