Which daughter element is produced from the beta decay of [tex]${}_{36}^{89} \text{Kr}$[/tex]?

A. [tex]${}_{35}^{89} \text{Br}$[/tex]

B. [tex][tex]${}_{37}^{89} \text{Rb}$[/tex][/tex]

C. [tex]${}_{34}^{85} \text{Se}$[/tex]

D. [tex]${}_{38}^{93} \text{Sr}$[/tex]



Answer :

In order to determine the daughter element produced from the beta decay of Krypton-89 ([tex]${ }_{36}^{89} Kr$[/tex]), we need to understand what happens during a beta decay process.

In beta decay, a neutron in the nucleus is converted into a proton, and a beta particle (an electron) is emitted. This results in an increase in the atomic number (number of protons) by 1 while the mass number (sum of protons and neutrons) remains unchanged.

Given:
- Original element: Krypton-89 ([tex]${ }_{36}^{89} Kr$[/tex])
- Atomic number (Z) = 36
- Mass number (A) = 89

Steps to find the daughter element:
1. Increase the atomic number by 1:
- The atomic number increases from 36 to 37.

2. Keep the mass number the same:
- The mass number remains 89.

Therefore, the daughter element will have:
- Atomic number: 37
- Mass number: 89

Checking the periodic table, the element with atomic number 37 is Rubidium (Rb). Thus, the daughter element after the beta decay of Krypton-89 is Rubidium-89 ([tex]${ }_{37}^{89} Rb$[/tex]).

So, the correct answer is:
B. [tex]${ }_{37}^{89} Rb$[/tex]