Which of the following selections completes the following nuclear reaction? a gamma ray plus 40 20 calcium becomes 39 20 calcium plus blank. a beta particle a neutron a positron an alpha particle gamma radiation

The Neutron ; ¹₀n

Explanation:

Let us have the equation;

Gamma ray + 40 20 Calcium ---> 39 20 calcium + blank

Rewriting our equation, we have;

⁰₀γ + ⁴⁰₂₀Ca → ³⁹₂₀Ca + A

We are to calculate what A is.

It is important to understand the following concepts;

Mass Number = Total number of Protons + Neutrons in an atom. It is usually represented by the superscript after the atom.

Atomic Number = Total number of Protons in an atom. It is usually represented by the subscript before the atom.

Total mass number;

Reactants = 0 + 40 = 40

Products = 39 + x

Total Atomic number;

Reactants = 0 + 20 = 20

Products = 20 + y

Since there have to be conservation of mass,

Reactant Mass Number = Product Mass Number

40 = 39 + x

x = 40 - 39 = 1

Reactant Atomic Number = Product Atomic Number

20 = 20 + y

y = 20 - 20 = 0

From our calculations we now know that A has atomic number of 0 and mass number of 1.

Only the Neutron fits this description.

The Neutron is; ¹₀n

Beta particle is ⁰₋₁e, Positron is  ⁰₁e, Gamma is ⁰₀γ and Helium is ⁴₂He

the answer is learned

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.