问答题 CaIculate the percent by mass and the molality in terms of CuSO4 for a solution prepared by dissolving 11.5g of CuSO4·5H2O in 0.1000kg of water. Remember to consider the water released from the hydrate.
【正确答案】Solution:  m(CuSO4)=[-11.5×159.6/249.68]g=7.35g
   m(H2O)=[11.5-7.35]g=4.15g
   Percent by mass: 7.35/(100.0+4.15)=0.071
   b=[-7.35/(159.6×0.1042)]mol·kg-1=0.442mol·kg-1
【答案解析】