Question

What is the gram formula mass of $KCl$?

Answer 1

Molar mass is the amount of a chemical compound required for $1$ atoms or $6.022 \times {10^{23}}$ atoms. Gram formula mass is the same as molar mass. When the molar mass of the chemical compound is expressed in grams it is called Gram Formula Mass.

Complete answer:
To calculate the gram formula mass of any substance, first, we multiply the molar mass of all the elements present in that substance by the respective number of atoms of that element present in that substance and simply add them up to get the mass of the whole substance or compound.
In $KCl$, there is only one atom of potassium and one atom of chlorine. We know that the molar mass of potassium is $39.1g/mol$ and the molar mass of chlorine is $35.45g/mol$.
Hence, to get the gram formula mass of $KCl$, we will multiply molar mass of potassium by one and molar mass of chlorine by one. To get the result, we will just add them up.
$1 \times 39.1g/mol + 1 \times 35.45g/mol$
$= 39.1 + 35.45g/mol$
$= 74.55g/mol$
Hence the molar mass of potassium chloride $(KCl)$ is $74.55g/mol$. To get the gram formula mass, we will just express the molar mass in grams. Therefore, the gram formula mass of $KCl$ is $74.55g$

Additional Information:
Potassium chloride is used for the manufacturing of fertilizer called potash. It can also act as a salt substitute for food, but it is usually mixed with ordinary salt to improve taste. It is used as a supplement in animal feed to boost the number of nutrients in the feed, which promotes healthy growth in animals.

Note:
Whenever you write the molar mass of any element or compound, do not forget to write the grams per mole or $g/mol$ at its end. $g/mol$is the SI unit of molar mass. However, when you write the gram formula mass, just use grams $(g)$ at its end. Sometimes, in a hurry, you might miss this little detail which can result in an incorrect answer.