Q. 25.0( 2 Votes )

An atom with atomic number 9 and mass number 19 will have the following constituents:
A. 9p, 9n, 9e

B. 9p, 10n, 9e

C. 10p, 9n, 9e

D. 9p, 9n, 10e

Answer :

We know that,


Atomic number = Number of protons = 9.


Hence, 9p


Mass number = Number of protons + Number of neutrons


19 = 9 + Number of neutrons


Number of neutrons = 19-9 =10


Hence, 10n


Now, Number of electrons = Number of protons


Number of electrons =9


Hence, 9e


Therefore the correct option is B

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Electronic Configuration34 mins
Atomic Number46 mins
Quiz | Bohr's-Bury Rule and Valency62 mins
How Radioactivity Works?29 mins
Valency31 mins
What an Atom holds?41 mins
Champ Quiz | Important Questions of Atom41 mins
Learn How to Write The FormulaFREE Class
Quiz | Check Your Concepts on An Atom34 mins
Get To Know Electronic Configuration35 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses