CBSE Class 11-science Answered
Equal masses of oxygen (O2) and ozone (O3) are taken seperately. choose the correct alternatives .(there are more than one correct)
(A)they contain equal number of oxygen atoms .
(B)they contain equal number of oxygen molecules.
(C) they occupy different volumes ( seperately)under the same conditions of temperature and pressure.
(D)under the same conditions of temperatures and pressure volume occupied by O2 and O3 are in 3:2 ratio .
1 mole of O2 = 32g
? moles of O2 = 1g
1 x 1/32 = 0.0312 moles = n1 ---------------------(1)
1 mole of O3 = 48g
? moles of O3 = 1g
1 x 1/48 = 0.0208 moles = n2 ---------------------(2)
So numbers of moles are different.
Solution for Option (C)
They occupy different volumes under the same conditions of temperature and pressure.
PV = n RT --------------------------------------------(3)
So V = n RT/P
When we calculate volume P, R and T will remain constant. But since number of moles are different so volumes of O2 and O3 will be different.
Solution for option (D)
Under the same conditions of temperature and pressure volume occupied by O2 and O3 are in the ratio 3:2.
Since P, R and T are constant.
So equation (3) can be written as follows
V1/V2 = n1/n2
V1/V2 = 0.0312/0.0208
Multiplying the equation by 100
V1/V2 = 3/2
So the ratio is 3:2