How is molecular weight related to the size of a molecule?
Genuinely in need of the answer to the following question. Thank you.
Molecular weight is indeed related to the size of a molecule. The molecular weight of a molecule is a numerical value calculated by adding up the atomic weights of all the atoms in the molecule. It is also known as the molar mass.
The atomic weight of an element is based on the average mass of its naturally occurring isotopes. Since atoms are extremely small, the atomic weights of individual atoms are generally expressed in atomic mass units (amu), which are based on the mass of a carbon-12 atom.
To determine the molecular weight of a molecule, you would need to know the chemical formula of the molecule, which indicates the types and number of atoms present. For example, the chemical formula for water is H2O, indicating that it consists of two hydrogen atoms and one oxygen atom.
To calculate the molecular weight of water, you would find the atomic weight of each element (hydrogen and oxygen) and multiply it by the number of atoms present. The atomic weight of hydrogen is approximately 1 amu, while the atomic weight of oxygen is approximately 16 amu.
Thus, the molecular weight of water would be (2 * 1 amu) + (1 * 16 amu) = 18 amu.
In general, molecules with higher molecular weights tend to be larger in size because they contain a larger number of atoms. This is because atoms are the building blocks of molecules, and as the number of atoms in a molecule increases, so does its size. However, it is important to note that molecular weight alone does not provide a direct measure of the physical size or shape of a molecule.