Explain quantitatively the order of magnitude difference between the diamagnetic susceptibility of `N_2(-5xx10^-9)` (at STP) and `Cu(-10^-5)`.

Explanation

We know that
Density of nitrogen ` rho_(N_(2))=(28g)/(22.4L)=(26g)/(22400c c)`
Also, density of copper `rho_(Cu)=(8g)/(22.4L)=(8g)/(22400c c)`
Now, comparing both densities
`(rho_(N_(2)))/(rho_(Cu))=(28)/(22400)xx(1)/(8)=1.6xx10^(-4)`
Also given `(X_(N_(2)))/( X_(Cu))=(5xx10^(-9))/(10^(-5))=5xx10^(-4)`
We know that, `X=("Magnetisation"(M))/("Magnetic intensity"(H))`
`=("Magnetic moment" (M)//"volume"(V))/(H)`
`=(M)/(HV)=(M)/( H("mass"//"density"))=(Mp)/( Hm)`
`X=rho (because (M)/(Hm)= "constant")`
Hence, `(X_(N_(2)))/(X_(Cu))=(rho_(N_(2)))/(rho_(Cu))=1.6xx10^(-4)`
Thus, we can say that magnitude difference or major difference between the diamagnetic susceptibility of `N_(2)` only Cu.