Answer:
A = 65.46 u
Explanation:
Given that,
The composition of zinc is as follows :
Zn-64 = 48.63%
Zn-66 = 27.90%
Zn-67 = 4.10%
Zn-68 = 18.75%
Zn-70 = .62%
We need to find the average atomic mass of the given element. It can be solved as follows :
So, the average atomic mass of zinc is 65.46 u.
Solution :
Given :
Amount of anserine solution = 0.200 M
pH value is = 7.20
Preparation of 0.04 M solution of anserine from the 0.2 M solution.
0.2 M x = 0.04 M x 1000 ml
= 200 ml
So the 200 ml of 0.2 M anserine solution is required to prepare0.04 M of anserine.
0.1 M x = 0.04 x 1000 ml
= 400 ml
Therefore, 400 ml of HCl is needed.