67th B.P.S.C. (Pre) 2021
Which of the following is an incorrect option?
aThe atom is electrically neutral due to the presence of protons and electrons inside the nucleus✓ Correct
bElectrons are negatively charged and have negligible mass
cAtomic number is the number of protons in an atom of an element
dIsotopes are useful as nuclear fuel, in the medical field, in carbon dating etc
eNone of the above / More than one of the above
Explanation
Among the given statements, option (a) is not correct, because an atom is electrically neutral due to an equal number of protons (positively charged particles) and electrons (negatively charged particles). However, the nucleus contains only protons and neutrons, while electrons are present in orbits outside the nucleus. The statements in options (b), (c), and (d) are correct.
general-science