Question

10克硝酸钾溶于90克水中,将此溶液均匀分成四份,1）一份溶液的百分比浓度（ ） 2）.往一份溶液中加入2.5克硝酸钾,

Answer 1

1 10/(10+90) = 10%

2 (2.5+2.5)/(25+2.5) = 18.2%

3 2.5/50 = 5%

4 (20*15%+2.5)/(25+20) = 12.2%