His purpose in making on-the-spot investigations of the James River was to find out whether its South Branch was deep enough to be used by large boats.
【简答题】(1)已知硫酸溶液的浓度越大密度也越大.和50%的H 2 SO 4 溶液等质量混合后,所得溶液溶质的质量分数______(填“大于”“小于”或“等于”)45%;如果是等体积混合,混合以后所得溶液溶质的质量分数______(填“大于”“小于”或“等于”)45%. (2)已知98%的浓H 2 SO 4 的物质的量浓度为18.4mol/L,试判 断49%的H 2 SO 4 溶液的物质的量浓度______...