What is the molecular weight of h2o?

1 Answer
Apr 12, 2018

18.01528 \ "u"

Explanation:

H_2O is water. It consists of two hydrogen atoms and one oxygen atom.

So, the molecular mass of H_2O would be the total mass of the two hydrogen atoms and one oxygen atom.

Looking at the periodic table, each hydrogen atom has a mass of 1.00794 \ "u", while each oxygen atom has a mass of 16 \ "u".

So, the total mass of a single water molecule will be:

2*1.00794 \ "u"+16 \ "u"

=18.01588 \ "u"

Looking at the actual value, it is supposedly 18.01528 \ "u", so we got a difference of +0.0006 \ "u".