Question

Which of the following is a property of elements $?$
(A) Element is made up of two or more kind of atoms
(B) Compounds combine to form elements
(C) They can be broken down into two or more simpler substances by physical means or by chemical means
(D) Properties of elements differ from those of their compounds

Answer 1

Hint : Everything that surrounds us is made up of matter. They can be classified into pure matter and impure matter. Pure matter has a fixed composition while impure does not. They do not have a fixed composition or fixed set of properties and are thus called mixtures. They are further classified into homogeneous and heterogeneous mixtures.

Complete Step By Step Answer:
Pure substances can be classified into elements and compounds. An element is a chemical material that consists of only one type of particle, which can be atoms or molecules. Hydrogen, nitrogen, sodium, mercury, gold, silver, neon etc. are all examples of elements.
Properties of elements are:o
Elements are made up of only a single kind of atom.
Elements combine to form compounds.
They cannot be broken down into two or more simpler substances by physical means or by chemical means.
Properties of compounds differ from those of their compounds.
Therefore the correct option is (D) Properties of elements differ from those of their compounds. For example, ${H_2}$ is a combustible gas and ${O_2}$ aids combustion. Water, ${H_2}O$ , which is formed by the reaction of two, is a fire extinguisher. ${H_2}O$ .

Note :
The main difference between an element and a compound is that the former is made up of only one type of atom while the latter consists of more than one type of atoms.
Elements are represented by symbols while compounds are represented by chemical or molecular formula.
Elements can be classified into three types- metals, non-metals and semiconductors.