Potassium has a mass of 39.1 amu. Chloride has a mass of 35.45 amu. By the law of conservation of mass, what is the mass of potassium chloride, when these two ions combine?

Feb 13, 2016

Simply atomic masses are to be added since the formula is KCl.

Feb 13, 2016

The atomic mass of $\text{KCl}$ is $\text{74.6 u}$, and its molar mass is $\text{74.6 g/mol}$.

Explanation:

Since the formula for potassium chloride is $\text{KCl}$, add the atomic masses of potassium and chlorine to determine the atomic mass of $\text{KCl}$.

$\text{Atomic mass KCl"="39.1 u + 35.45 u"="74.6 u}$

The molar mass of one formula unit of $\text{KCl}$ is $\text{74.6 g/mol}$.