Answer : Average atomic weight of copper atoms will be
63.62 u.
Explanation : For calculating average atomic weight for any given atom we use this formula,
m = Σ

X % abundance
where, m - avg atomic mass of isotope.
and

- mass of isotope
on solving we get,
m = [63 u X (69/100)] + [65 u X (31/100)] = 63.62 u.
Answer : Half reaction is defined as the reaction which will be <span>either the oxidation or reduction </span>reaction<span> of particular species in a given redox </span>reaction<span>.
So as per the definition in the reaction of,
</span>

<span>
</span>

<span>
here on left and right side </span>

will get cancelled.
and we will get,

Here,

...this is oxidation reaction as Ba is getting reduced to

by losing 2 electrons.
whereas,on the other hand,

...this is reduction reaction as

is getting reduced to Zn by gaining 2 electrons.
Answer: Use the titration formula
Explanation: