hu
4. The average atomic mass of copper is 63.55 amu. If the only two isotopes of
copper have masses of 62.94 amu and 64.93 amu, what are the percentages of
each?
Answers
Answer:
copper has two naturally occurring isotopes, copper-63 and copper-65. This means that their respective decimal abundance must add up to give 1.
If you take x to be the decimal abundance of copper-63, you can say that the decimal abundance of copper-65 will be equal to 1−x.
Therefore,
Copper-63x⋅62.9296u+ copper-65(1−x)⋅64.9278u=63.546u
Solve this equation for x to get
62.9296⋅x−64.9278⋅x=63.546−64.9278
1.9982⋅x=1.3818⇒x=1.38181.9982=0.69152
This means that the percent abundances of the two isotopes will be
● 69.152%→63Cu
● 30.848%→65Cu
Explanation:
here is your answer please mark me in brainlist and give me many thanks please.
As we all know, Copper consist of two isotopes:-
- copper-63
- copper-65
On the basis of this, we can infer that the sum of their respective decimal abundance is 1.
Now, let x be the decimal abundance of copper-63
∴ decimal abundance of copper-65 = 1 − x
Now, [Copper-63x ⋅ 62.9296 u] + [copper-65(1−x) ⋅64.9278 u] = 63.546 u
To find the value of x, we will have to solve the following equation;
[62.9296 ⋅ x − 64.9278 ⋅ x] = [63.546 − 64.9278]
⇒ 1.9982 ⋅ x = 1.3818
⇒ x = 1.3818 ÷ 1.9982
⇒ x = 0.69152
∴ The percentages of abundances of each of the two isotopes are;
69.152% = 63 Cu
30.848% = 65 Cu
Ans) 69.15% = 63Cu; 30.84% = 65Cu