# Homework Help: Conservation of charge problem

1. Aug 30, 2010

### SarahJ3

1. The problem statement, all variables and given/known data
Which of the following reactions could not occur because they would violate conservation of charge

(n=neutron, p=proton, e- = electron, he^2+ = the helium nucleus)

a) p -> n + e-
b) n -> p + e-
c) He^2+ + He^2+ -> He^2+ p + n
d) p + He^2+ -> He^2+ + e-
e) p + p + e- -> p + p + p + X^-1 + Y^-1 + n (where x and y are various particles having the charges indicated).

cant figure out how to solve these, please help solve them as I learn best by example.
cant find an example in my book and I have no idea how to even attempt to solve it.
thanks!
:)

2. Relevant equations
n/a

3. The attempt at a solution
n/a No idea.

2. Aug 31, 2010

### Ed Aboud

Hi Sarah,

Ok so I think you should revise the principle of conservation of charge.

In this case, a useful approach would be to remember that the charge on the left hand side of an equation is equal to the charge on the right hand side of the equation.

For example, analyse question a) p -> n + e-

What is the charge of a proton 'p' , neutron 'n' and electron 'e'?