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?

2 Answers
Feb 13, 2016

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

Feb 13, 2016

The atomic mass of #"KCl"# is #"74.6 u"#, and its molar mass is #"74.6 g/mol"#.

Explanation:

Since the formula for potassium chloride is #"KCl"#, add the atomic masses of potassium and chlorine to determine the atomic mass of #"KCl"#.

#"Atomic mass KCl"="39.1 u + 35.45 u"="74.6 u"#

The molar mass of one formula unit of #"KCl"# is #"74.6 g/mol"#.