2NaOH+H2SO4==Na2SO4+2H2O
80 9 142
50*8% X Y
80/(50*8%) = 98/X = 142/Y
X = 4.9g,Y = 7.1g
所以反应前硫酸溶液中溶质的质量=4.9g
生成硫酸钠质量=7.1g