Question: The molecular formula of glucose is \[{C_6}{H_{12}}{O_6}\]. Calculate its molecular mass. \[(Atomic ...

Question

The molecular formula of glucose is ${C_6}{H_{12}}{O_6}$ . Calculate its molecular mass. $(Atomic Mass:C = 12u;H = 1u;O = 16u)$

Answer 1

Solution

Let us first be clear that the main difference between atomic mass and molecular weight is that atomic mass refers to the mass of a single atom, whereas molecular weight refers to the total weight of all the atoms in a molecule. Atoms are the fundamental constituents of all substances. Atomic mass is the weight of an atom. We can also say that atomic mass is simply the mass of an atom.

Complete answer:
We need to know that protons, neutrons, and electrons make up the majority of atoms. The mass of an atom is known as atomic mass. It is, in other words, the sum of the masses of all neutrons, protons, and electrons in a single atom when the atom is not moving (rest mass).
A molecule's molecular weight is the sum of the weights of all its atoms. This is the number of atoms, molecules, or compounds in one mole of the substance. It is the mass of the Avogadro number of atoms/molecules or compounds, in other words.
To find the molecular mass of a compound:
The first thing we need to do is to find the individual atomic masses for each element, present in the compound which is glucose in this case and also the atomic masses are given.
We need to count how many atoms there are for each element. In this case, six carbon, twelve hydrogen and six oxygen.
We then find the masses of all the atoms of elements and add them.
$Atomic mass of C = 12u$
$Atomic mass of H = 1$
$Atomic mass of O = 16u$
$Therefore,molecular mass of{C_6}{H_{12}}{O_6}$ ,
$(6 \times 12) + (12 \times 1) + (6 \times 16) = 180g/mol$

Note:
We must note that the mass of atoms is determined by atomic mass, while the mass of molecules is determined by molecular weight. The molecular weight is the total of the weights of the atoms in the molecule, whereas the atomic mass is the mass of a single atom. Another notable distinction between atomic mass and molecular weight is that atomic mass is measured in amu, whereas molecular weight is measured in g/mol.