称取不纯草酸(H2C2O4)样品0.1140克,溶于水后以酚酞为指示剂,用0.1024mol⼀L NaOH标

2025-02-22 22:43:16
推荐回答(1个)
回答1:

解:设样品中H2C2O4的质量为X
23.76ml氢氧化钠溶液中含氢氧化钠的物质的量=0.1024mol/L*0.02376L=0.002433024mol

2NaOH + H2C2O4= Na2C2O4+2H2O

2 90.04
0.002433024mol X

X=0.10953g
样品中H2C2O4的百分含量=0.10953g/0.1140g*100%=96.08%