Chemistry

[Math wizard]

How many moles of Hydrogen are in H2O when H2O has a mass of 100?

[Iota]

How many moles of Hydrogen are in H2O when H2O has a mass of 100?

 

I laughed when I saw your post's title 'Chemistry' under the 'Maths' forums. Chemistry could go in chemistry forums .<br class="Apple-interchange-newline">

 

100g of 18gmol^-1 H₂O.

 

100/18= 5.56 mol H₂O.

 

(2/18)*100= 11.11% H by mass in H₂O. (Because 2gmol^-1 out of 18gmol^-1 Water is Hydrogen.)

 

(5.56/100)*11.11= 0.618mol H in H₂O. (Times by the percentage of water made up by Hydrogen by mass equals ANS.)

 

I'm confident this is the answer, but am doubting myself a bit, purely because it's been a while since I've done these sorts of chemistry calculations. It all seems to pan out, logically.