Composition of the nuclei of two atomic species X and Y are given below : Give the mass number of X and Y. What is the relation between the two species ?

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Chapter 4

NCERT

Class 9

Science

Solutions

13. Composition of the nuclei of two atomic species X and Y are given below :

Question:

Composition of the nuclei of two atomic species X and Y are given below :

	X	Y
Protons	6	6
Neutron	6	8

Give the mass number of X and Y. What is the relation between the two species ?

Answer:

Mass number = Number of Proton Number of Neutron

Mass number of Y = 6 + 6 = 12

Mass number of Y = 6 + 8 = 14 and Atomic number = Number of Proton

Atomic number of X = 6

Atomic number of Y = 6

Since, X and Y have same atomic number but have different mass number so they are isotopes.

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