下载APP
【简答题】
Na 2SO 3·7H 2O是食品工业中常用的漂白剂、抗氧化剂和防腐剂。Na 2SO 3在30℃时的溶解度为35.5g/100gH 2O。 1）计算30℃时Na 2SO 3饱和溶液中Na 2SO 3的质量分数
。（保留2位小数） 2）计算30℃时271g Na 2SO 3饱和溶液中水的质量。 3）将30℃的Na 2SO 3饱和溶液271g冷却到10℃，析出Na 2SO 3·7H 2O晶体79.5g。计算10℃时Na 2SO 3在水中的溶解度。
举报
参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】If those "mad moments"— when you can’t recall what your friend has told you or where you left your keys—are becoming more frequent, mental exercises and a healthy brain diet may help. Just as bodies r...
A.
everyone can be forgetful sometimes regardless of one’s age
B.
we can prevent our sound mind from aging with certain methods
C.
brain aging starts from the time when we are in our 20s and 30s
D.
memory loss is a sign that shows we are getting old
【单选题】已知Ca 3 (PO 4 ) 2 的饱和溶液中,c(Ca 2+ )=2.0×10 -6 mol/L, c(PO 4 3- )=2.0×10 -6 mol/L,则Ca 3 (PO 4 ) 2 的K sp ɵ 为()。
A.
2.0×10-29
B.
3.2×10 -12
C.
6.3×10 -18
D.
5.1×10 -27