Question

Gram Atomic mass is just the atomic mass expressed in grams ...ie, atomic mass with gram as units. Our book says that gram atomic mass and gram atom are the same thing (similarly for gram molecule and gram molecular mass) . But later a formula is given that : Gram atom = mass in grams / Atomic mass [RAM].

There are questions also that use this formula ( similarly for gram molecule) in which we have to find the number of "gram atoms " in a given mass of substance.

So what is the real meaning of gram atom and the formula ( and is is similar for gram molecules) ?

Answer 1

dear student,

first you understand that, gram atom and gram atomic mass are not exactly same thing.

book actually means that, 1"gram atom"of an atom contains gram atomic mass of that atom.

Ex:-
1gram atom of oxygen contain 16g atomic mass.

that is if given mass of oxygen is 16g. Then it is equal to 1gram atom of oxygen.


◎ if the given mass of atom is not equal to its gram atomic mass, We have to use that formula to find No. Of gram atom.

No. Of Gram atom = mass in grams / gram Atomic mass.

Ex :-
if given mass of oxygen is 32g. We have to find no. Of gram atom.
We already know gram atomic mass of oxygen is 16.

​​​​​​then use formula,

no. of gram atom = mass in gm / gram atomic mass = 32 /16 =2.

similiar in case of gram molecules too.👍👍



​​​​