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Question
Which of the following are true for an element?
- Atomic number = number of protons + number of electrons
- Mass number = number of protons + number of neutrons
- Atomic mass = number of protons = number of neutrons
- Atomic number = number of protons = number of electrons
Options
(i) and (ii)
(i) and (iii)
(ii) and (iii)
(ii) and (iv)
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Solution
(ii) and (iv)
Explanation -
Mass number = p + n
Atomic number = p = e
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