An atom contains 3 protons, 3 electrons and 4 neutrons

CBSE Class 9 CBSE Class 9 Science
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1

An atom contains 3 protons, 3 electrons and 4 neutrons. Find its atomic number, mass number and valency.

2

Atomic number = Number of protons = 3
Mass number = Number of protons + number of neutrons =3 + 4 = 7
Electronic configuration of the atom is 2,1(K,L)
Hence, its valency is 1.