Answer:
45
Explanation:
There are 12 Carbons
There are 22 Hydrogens
There are 11 Oxygens.
I think the answer is either 0 or 45. But the wording is very sloppy. It is not really atoms that are present. There are ions.
Go with 45 but hold your nose when writing your answer.
You use the equation M1V1=M2V2 for dilution problems
(250)3=.5x
x= 1500 mL
The neutron is inside the nucleus