如果配制1升溶液柠檬酸的用量是0.05×192=9.6克根据PH=PKa-lg[H2A-]/[HA2-]4.5=4.77-lg[H2A-]/[HA2-]lg[H2A-]/[HA2-]=0.27[H2A-]/[HA2]=1.86/1[H2A]=0.05×1.86/2.86=0.0325mol[HA2]=0.05×1/2.86=0.0175mol 需要氢氧化钠的质量是（0.05+0.0175）×40=2.7克...