Question

determining the composition of an atom

1. calculate the number of protons, neutrons and electrons in an atom of boron below:

$_{5}^{11}b$

Explanation:

Step1: Identify atomic number and mass number

The symbol $_5^{11}B$ indicates that the atomic number ($Z$) of boron is 5 and the mass number ($A$) is 11.

Step2: Calculate number of protons

The atomic number is equal to the number of protons. So, the number of protons ($p$) is 5. $p = 5$

Step3: Calculate number of neutrons

The mass - number is the sum of protons and neutrons. So, the number of neutrons ($n$) is $A - Z$. $n=A - Z=11 - 5 = 6$

Step4: Calculate number of electrons

For a neutral atom, the number of electrons ($e$) is equal to the number of protons. So, $e = 5$

Answer:

Number of protons: 5, Number of neutrons: 6, Number of electrons: 5