(1)1.792L (2)解:FeS + 2HCl = FeCl 2 + H 2 S ↑ 88g 2mol 8.8g 0.21L×2.0mol/L 所以盐酸过量 n(Fe 2+ ) = n (FeCl 2 )= n (FeS) = 8.8g ÷ 88g/mol =0.10mol c(Fe 2+ ) = 0.10mol ÷ 0.20L =0.50 mol/L n(H + ) = n (HCl )总 -n (HCl )反应 = n (HCl )总 -2n (FeCl 2 )= 0.21L×2.0 mol/L-2× 0.10mol =0.20mol c(H + ) = 0.20mol ÷ 0.20L = 1.0mol/L 答:溶液中Fe 2+ 和H + 的物质的量浓度分别为0.50mol/L和1.0mol/L |