Question

which represents the balanced nuclear equation for the beta plus decay of c - 11?
¹¹₆c → ¹¹₅b + ⁰₊₁e
¹¹₆c → ¹¹₇n + ⁰₊₁e
¹¹₆c → ¹¹₇n + ⁰_-1e
¹¹₆c → ¹¹₅b + ⁰_-1e

Explanation:

Step1: Recall beta - plus decay concept

In beta - plus decay, a proton in the nucleus is converted into a neutron, a positron ($_{+1}^{0}e$), and a neutrino. The atomic number (number of protons) decreases by 1 and the mass number (sum of protons and neutrons) remains the same.

Step2: Analyze carbon - 11 decay

Carbon - 11 ($_{6}^{11}C$) has an atomic number of 6 and a mass number of 11. After beta - plus decay, the atomic number will be $6 - 1=5$ and the mass number will remain 11. The resulting nucleus is boron - 11 ($_{5}^{11}B$) and a positron ($_{+1}^{0}e$) is emitted. The balanced nuclear equation is $_{6}^{11}C
ightarrow_{5}^{11}B + _{+1}^{0}e$.

Answer:

$_{6}^{11}C
ightarrow_{5}^{11}B + _{+1}^{0}e$ (the first option)