Balance this nuclear reaction by supplying the missing nucleus: 249/98 cf +__ --> 263/106 sg +4 1/0 n

the missing nucleus is an isotope of oxygen 18/8 O

Explanation:

Since the reacting mass must be equal to the resulting mass

That is right hand side must be equal to the left

We check the total number of reacting moles in the equation

On the right hand we have 267/106

On the left hand side we have 249+x/98+x

Equation both we have

249+ x/98+y = 267/106

Therefore x = 18

y = 8

This is an isotope of oxygen

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a