Question

The composition of two atomic particles is given below :

$\begin{array}{ccc}& & \\ X& Y& \\ \text{Protons}:& 8& 8\\ \text{Neutrons}:& 8& 9\\ \text{Electrons}:& 8& 8\end{array}$

(i) What is the mass number of X ?

(ii) What is the mass number of Y ?

(iii) What is the relation between X and Y ?

(iv) which element/elements do they represent?

Answer 1

(i) Mass number of X = no. of protons + no. of neutrons = 8 + 8 =16

(ii) Mass number of Y = no. of protons + no. of neutrons = 8 + 9 =17

(iii) X and Y are isotopes since they have same atomic number.

(iv) X and Y represent Oxygen since oxygen has Atomic number = 8.