How would you go about the solving this?

Question

The fission of plutonium reaction is written as follows. One neutron combines with Pu-239 on the left side of the reaction. The products on the right side are one atom of xenon-134

(Xe-134), 3 neutrons, and an atom of one other element labeled here with the symbol “Q”. Identify “Q” and calculate its values of “A” and “N”.

Answer 1

The fission of plutonium reaction is written as follows. One neutron combines with Pu-239 on the left side of the reaction. The products on the right side are one atom of xenon-134

(Xe-134), 3 neutrons, and an atom of one other element labeled here with the symbol “Q”. Identify “Q” and calculate its values of “A” and “N”.

Let The reaction be

₀n¹ +₉₄ Pu ²³⁹ =₅₄ Xe ¹³⁴ +3 ₀n¹ +_AQ^B

I have plugged in some values from my side to complete the question

94+0 = 54 +0 + A

So A = 94-54

=40

and 1+239 = 134 +3 +B

240 = 137 +B

Gives B= 240 -137 =103

But B = A + N

N = B -A

103 - 40 = 63 = Number of Neutrons

So _A Q ^B = ₄₀ Q¹⁰³

So Q is ₄₀Zr ¹⁰³ = Isotope of Zr with 40 protons and 63 neutrons