[shaqtus]

I have a question here:

Which of the following shows conservation of charge?
A) Cu²⁺ + 2e^-  ==>  Cu
B) Cu⁺  ==>  Cu + e^-
C) Cu²⁺  ==>  Cu + 2e^-

Please explain the answer because all of these choices seem right to me.

[Grundalizer]

Conservation of charge means that the LEFT side of the equation and the RIGHT side of the equation have the same total charge.

Let's look at A, it has a +2 charge and 2 -1 charges, so it has a net charge of 0 on the left and 0 on the right.

Let's look at B, the left side has +1, the right side has -1, although they "sum to zero" they are on Opposite sides of the arrow, so the left and right sides DO NOT have the same charge.

let's look at C, the left side has 2+ and the right side has 2-, although that sums to zero, one side has a different net charge than the other side.

Conservation of charge states that both sides must have the SAME net charge, not just charges that add to zero.

Therefore, A is the correct answer because the left side has the same net charge as the right side.