Question

The number of gram atoms of oxygen present in 0.3 gram mole of (COOH)2.2H2O is

Answer 1

simply, 1 mole of (COOH)2.2H2O has 6 moles of Oxygen atoms. (adding them up)
therefore by using unitary method, if 1 mole contain 6 mole O atoms, 0.3 moles will contain 0.3×6 moles of atoms , I.e. 1.8 moles of Oxygen atoms.
NOTE - GRAM ATOM, GRAM MOLECULE,GRAM MOLES are all MOLES.

Answer 2

Answer : The number of gram atoms of oxygen present in 0.3 gram mole of $(COOH)_2.2H_2O$ is, 1.8 gram atoms

Solution :

$(COOH)_2.2H_2O$ in this compound, there 2 atoms of carbon, 6 atoms of oxygen and 6 atoms o hydrogen.

As, 1 gram mole of $(COOH)_2.2H_2O$ contains = 6 gram atom of oxygen

So, 0.3 gram mole of $(COOH)_2.2H_2O$ contains = $6\times 0.3=1.8$ gram atom of oxygen

Therefore, the number of gram atoms of oxygen present in 0.3 gram mole of $(COOH)_2.2H_2O$ is, 1.8 gram atoms