Question

Which of the following symbols of elements are incorrect? Give their correct symbols.

• A. Cobalt $\mathrm{CO}$
• B. Carbon $\mathrm{c}$
• C. Aluminum $\mathrm{AL}$
• D. Helium $\mathrm{He}$
• E. Sodium $\mathrm{So}$

Answer 1

Answer: (A), (B), (C), (E)

Sodium $\mathrm{So}$

Explanation for the correct options:

A) Cobalt $\mathrm{CO}$

$\mathrm{CO}$ is not the correct symbol of cobalt. If the symbol of an element contains two letters, the first letter should be always in a capital letter and the second letter should be in a small letter. Therefore, the symbol of cobalt is $\mathrm{Co}$, not $\mathrm{CO}$.

B) Carbon $\mathrm{c}$

$\mathrm{c}$ is not the correct symbol of carbon. If an element has a single letter as a symbol, it should be written in the capital letter. Hence, the symbol of carbon is $\mathrm{C}$, not $\mathrm{c}$.

C) Aluminium $\mathrm{AL}$

$\mathrm{AL}$ is not the correct symbol of aluminum. If the symbol of an element contains two letters, the first letter should be always in a capital letter and the second letter should be in a small letter. Therefore, the symbol of aluminum is $\mathrm{Al}$, not $\mathrm{AL}$.

E) Sodium $\mathrm{So}$

Some of the symbols of the elements are derived from Latin, German or Greek words. Sodium is derived from the Latin word “natrium”. Therefore, the first two letters from the word “natrium” is the symbol of sodium. Hence, $\mathrm{Na}$ is the symbol of sodium.

Explanation for the incorrect Option:

D) Helium $\mathrm{He}$

He is the correct symbol of the element helium. If the symbol of an element contains two letters, the first letter should be always in a capital letter and the second letter should be in a small letter. Hence, $\mathrm{He}$ is correct.

Hence, the options (A), (B), (C), and (E) are correct.