(1)25mL氢氧化钠溶液中溶质质量为
25mL×1.2g/mL×10%=3.0g
答:氢氧化钠溶液中溶质的质量是3.0g
(2)设食醋中醋酸的质量为x.
CH 3COOH+NaOH=CH 3COONa+H 2O
60 40
x 3.0g
60
x =
40
3.0g
解之得:x=4.5g
所以食醋中醋酸的质量分数=
4.5g
100g ×100% =4.5%
答:食醋中醋酸的质量分数为4.5%
(1)25mL氢氧化钠溶液中溶质质量为
25mL×1.2g/mL×10%=3.0g
答:氢氧化钠溶液中溶质的质量是3.0g
(2)设食醋中醋酸的质量为x.
CH 3COOH+NaOH=CH 3COONa+H 2O
60 40
x 3.0g
60
x =
40
3.0g
解之得:x=4.5g
所以食醋中醋酸的质量分数=
4.5g
100g ×100% =4.5%
答:食醋中醋酸的质量分数为4.5%