Q. Let An be the area enclosed by the nth orbit in a hydrogen atom. The graph of ln (An/A1) against In (n)
(a) will not pass through origin
(b) will be a straight line with slope 4
(c) will be a rectangular hyperbola
(d) will be a parabola
Ans: (b)
Sol: An = π rn2
An = π(r0n2)2
Hence , An = πr02n4 = A1r4
An/A1 = n4
Taking log ,
ln(An/A1) = 4ln(n)
Hence Straight line with slope 4 .