Question

Which of the following are true for an element? (i) Atomic number = number of protons + number of electrons (ii) Mass number = number of protons + number of neutrons (iii) Atomic mass = number of protons = number of neutrons (iv) Atomic number = number of protons = number of electrons

Answer 1

Answer:

2 option is correct for the following questions

Answer 2

The correct option is  (ii) Mass number = number of protons + number of neutrons.

• An atom has protons, neutrons, and electrons present inside it.
• To maintain electrical neutrality, the number of protons is equal to the number of electrons present in it.
• The number of neutrons may or may not be equal to the number of protons in a neutral atom.
• The mass number is simply the sum of the number of protons and neutrons present in the atom. (Since electrons do not contribute much to the mass.)
• The atomic number gives the number of protons present in the neutral atom.