Question

向100ml0.5mol/l的Na2CO3溶液中加入一定体积1mol/l的盐酸,恰好完全反应.

Answer 1

设所用1mol/l的盐酸物质的量是x mol

Na2CO3 + 2HCl = 2NaCl + CO2 (g) + H2O

1 2

0.1*0.5 x

1 :2 = 0.05 :x

x = 0.1 mol

1mol/l的盐酸体积:0.1 /1 = 0.1 L = 100 mL

1.反应前后溶液体积:100 + 100 = 200 mL = 0.2 L

Na+的物质的量:0.1 * 0.5 *2 = 0.1 mol

溶液中Na+的物质的量的浓度:0.1/0.2 = 0.5 mol/L

2.1*0.5/0.1 = 5 L