Arrange the following in order of increasing mass

I. 1 mole of N$$_2$$

II. 0.5 mole of O$$_3$$

III. $$3.011\times10^{23}$$ molecules of O$$_2$$

IV. 0.5 gram atom of O$$_2$$

63 g of a compound (Mol. Wt. = 126) was dissolved in 500 g distilled water. The density of the resultant solution as 1.126 g/ml. The molarity of the solution is

How much solid oxalic acid (Molecular weight 126) has to be weighed to prepare 100 ml. exactly 0.1 (N) oxalic acid solution in water?

$${C_6}{H_6}(liq) + {{15} \over 2}{O_2}(g) \to 6C{O_2}(g) + 3{H_2}O(liq)$$

Benzene burns in oxygen according to the above equation. What is the volume of oxygen (at STP) needed for complete combustion of 39 gram of liquid benzene?