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 (a) (i) and (ii) (b) (i) and (iii) (c) (ii) and (iii) (d) (ii) and (iv)
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Solution:
Answer is (d) (ii) and (iv)
Explanation:
Atomic number Z is the number of proton present in an electron which is also equal to number pf electron in an atom. Since the mass of neutron is negligible. Number of protons and electron are added to obtain mass number of an element.
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