chem ques

乖学生

a sample of 0.025 mole of the chloride of an element Z was dissolved in distilled water and the solution made up to 500cm^3. 12.5cm^3of this solution reacted with 25cm^3 of 0.1 mole dm^-3 silver nitrate solution. What is the most likely formula of the chloride?

A. Z2Cl        B. ZCl           C. ZCl4      D. ZCl5

meiling

我觉得是C。。
不太确定。。
答案呢？

乖学生

回复 2# meiling


    没有答案的，老师才刚分给我们做而已。。。
你怎样算到的?

四月一日的小皮

sample of 0.025 mole of the chloride of an element Z was dissolved in distilled water and the solution made up to 500cm^3. 12.5cm^3of this solution reacted with 25cm^3 of 0.1 mole dm^-3 silver nitrate solution.
Concentration of the Z solution
= 0.025/0.5 = 0.05mol dm-3
mole of Z solution = 0.05 x 12.5 / 1000 = 0.000625 mol
mole of AgNO3 = 0.1 x 25 /1000 = 0.0025 mol
0.000625 mol of Z solution react with 0.0025 mol of AgNO3
SO, 1 mol of Z solution react with  4 mol of AgNO3.
since there is 4 mole of Ag+ ion, it will nd to react with 4 mol of Cl- to form AgCl.
So, Z solution should have 4 Cl-.
ZCl4 is the answer.

孤风幻影