Question

The isotope of an atom containing 31 protons and 39 neutrons suddenly has two neutrons added to it. What isotope is created?
A.Yttrium-72
B. Gallium-41
C. Gallium-72
D. Yttrium-41

Answer 1

the isotope is identified by its Mass Number. Here the mass number increases by 2.

Answer 2

Do you know what the Mass Number is?

Answer 3

@welshfella look

Answer 4

The mass number of the original atom = 31 + 39 = 70
after adding 2 the new mass number is 72.
The atom is identified by its Atomic number which = number of protons (31)
You can find the name atom it is from the periodic table of elements.

Answer 5

http://www.ptable.com/

Answer 6

you'll find it on that link.

Answer 7

@welshfella your correct thank you