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"#.