【单选题】用高锰酸钾法测定硅酸盐样品中Ca2+的含量。称取样品0.5972g,在一定条件下,将Ca2+沉淀为CaC2O4,过滤,洗涤沉淀,将洗涤的CaC2O4溶于稀硫酸中,用c(KMnO4)=0.05052mol/L的KMnO4标准溶液滴定,消耗25.62mL,硅酸盐中Ca的质量分数为()。已知M(Ca)=40.00g/mol
【单选题】用高锰酸钾法测定硅酸盐样品中Ca2+的含量。称取样品0.5972g,在一定条件下,将Ca2+沉淀为CaC2O4,过滤,洗涤沉淀,将洗涤的CaC2O4溶于稀硫酸中,用c(KMnO4)=0.05052mol/L的KMnO4标准溶液滴定,消耗25.62mL,计算硅酸盐中Ca的质量分数().已知MCa=40g/moL.
【单选题】用高锰酸钾法测定硅酸盐样品中Ca 2+ 的含量。称取样品0.5972g,在一定条件下,将Ca 2+ 沉淀为CaC 2 O 4 ,过滤,洗涤沉淀,将洗涤的CaC 2 O 4 溶于稀硫酸中,用c(KMnO 4 )=0.05052mol/L的KMnO 4 标准溶液滴定,消耗25.62mL,硅酸盐中Ca的质量分数为 ( )。已知M (Ca)=40.08g/mol。
【单选题】A study comparing prices in 150 major cities has found that cities in Western Europe have become more expensive to live in since the full introduction of the euro currency (货币). The report also noted ...
A.
The economic development in Europe.
B.
The results of a study.
C.
Living costs outside the euro zone.
D.
Changes in world currencies.