Question

Choose the incorrect statement/statements from the following:

(i) Atomic mass of hydrogen is 1 u.
(ii) Atomic mass of helium is 2 u.
(iii) Atomic mass of chlorine is 17 u.
(iv) Atomic mass of phosphorous is 31 u.

• A. Statement (i), (ii) and (iii) are incorrect.
• B. Statement (i), (ii) and (iii) and (iv) are incorrect.
• C. Statement (i) and (iv) are incorrect.
• D. Statement (ii) and (iii) are incorrect.

Answer 1

The correct option is D

Statement (ii) and (iii) are incorrect.

The atomic mass of an element is expressed by considering $\frac{1}{12}$ the mass of an atom of carbon-12 (C-12) isotope as one unit. It is represented by the symbol 'u'. The atomic mass of few elements is given below:

Clearly, statements (ii) and (iii) are incorrect.