Question

Classify the following into elements and compounds:

Water, Hydrogen, Salt, Gold, Carbon dioxide, Iron

• A. (i, iii, iv) – A, (ii, v, vi) - B
• B. (i, iii, v) – A, (ii, iv, vi) - B
• C. (i, ii, v) – A, (iii, iv, vi) - B
• D. (i, ii, iii) – A, (iv, v, vi) - B

Answer 1

The correct option is B

(i, iii, v) – A, (ii, iv, vi) - B

Elements are pure substances which are composed of only one type of atom. Compound are substances which are formed by two or more different types of elements that are united chemically in fixed proportions

Water ($H_{2}O$ ) is composed of hydrogen and oxygen. Therefore, it is a compound. Hydrogen is an element. Salt (NaCl) is composed of sodium and chlorine. Therefore it is a compound.

Gold is an element. Carbon dioxide is composed of carbon and oxygen. Therefore, it is a compound. Iron is an element.