Question

What is matter that has only one kind of atom?
A) Molecule
B) Element
C) Cation
D) None of these

Answer 1

Hint: By looking at the periodic table, it is easy to say that the elements present in it are made up of similar atoms. Sometimes, molecules can also be made up of one type of atom but we need to look at all the options before answering.

Complete answer:
We have to know that the matter can be of three forms Solid, Liquid and Gas.
Option A) this is an incorrect option, but for many of you it seems to be right as if we see Chlorine molecule having chemical formula \[C{l_2}\], is made up of only one kind of atom i.e. \[Cl\].So for many of you this option seems to be right, but what if we look at other molecules.
For example, when we look at \[{H_2}O\] molecule it is made up of two types of atom one is \[H\] and other is \[O\] thus defining molecule as made up of only one kind of atom is not true in this case. Thus we can neglect this option.
Option B) this is a correct option as the matter that is made up of only one kind of atom, can be termed as Element.
For Example: \[Na\],\[Cu\].
The elements placed in the periodic table are made up of only one type of atom.
Option C) this option is incorrect as Cation is a polyatomic ion it cannot be considered as matter.
Option D) this is an incorrect option

So, Option B as correct.

Note:
We also know that the element present in the periodic table is the one which is made up of only one kind of atom. We also remember that in solids, particles are strongly packed even if they cannot be compressed easily. In liquids, particles are free to move around the container, but the particles will move more frequently in case of liquids. In gases, particles are free to move anywhere in the container and therefore can be compressed easily.