Two substances A and B are of equal masses and their molecular masses are in the proportions of 2:3. what is the ratio of the numbers of their molecules?

Explanation

From the question, `M_(A):M_(B)=2:3`, where `M_(A) and M_(B)` are the molecular masses of A and B respectively.
Now, let the mass of Amass of B= W g.
Number of molecules present in 1 gram-mole of any-substance`=6.022xx10^(23)`
Number of molecules in W g off `A=(W)/(M_(A))xx6.022xx10^(23)` and that in W g of `B=(W)/(M_(B))xx6.022xx10^(23)`
`therefore ("Number of molecules in W g of A")/("Number of molecules in W g of B")`
`=(W)/(M_(A))xx6.022xx10^(23)+(W)/(M_(B))xx6.022xx10^(23)=(M_(B))/(M_(A))=(3)/(2)`.