Question

What is the mass of one atom of calcium?

Answer 1

Hint: Every atom is composed of a nucleus and this nucleus is made up of protons and neutrons where protons is positively charged and neutrons are neutral in charge and electrons which are negatively charged are revolving around the nucleus.

Complete answer:
Calcium is a chemical element represented by the symbol $Ca$. calcium is kept in the category of alkaline earth metals and known as very reactive metal as it forms a dark oxide nitride layer when it gets exposed in air. It is the fifth most abundant element present in the earth crust.
Atomic number of calcium is 20 and the molar mass of the calcium is given by 40g/mol where mole is generally represented by the symbol mol. It is generally described as the unit of measurement for the amount of substance in SI where SI stands for International System of units. It is defined on the basis of Avogadro’s number.
A mole of a substance or particle can be defined as containing exactly $6.02214076\times {{10}^{23}}$ particles which may be atoms, molecules or ions where $6.02214076\times {{10}^{23}}$ is known as the Avogadro’s number.
We know that the mass of one atom is the same as the molar mass of the compound.
Here, the molar mass of the calcium is 40 g/ mol. This concludes that the mass of one atom of calcium would be 40 g.

Note:
The molecular formula is defined as the formula derived from molecules and is representative of the total number of individual atoms present in a molecule of a compound. A molecular formula generally uses a subscript which reports the actual number of each type of atom in a molecule of the compound.