What is the maximum number of emission lines when the excited electron of H atom in n = 6 drops to the ground state ?

Explanation

We know that No. of lines produced when an electron in 6th orbit to ground state.
`= ((n _(2) - n _(1)) ( n _(2) - n _(1) + 1 ))/( 2) = ( ( 6-1) ( 6-1+1))/( 2 ) = ( 5 xx 6)/(2) = 15` lines `(because n _(2) = 6, n _(1) =1)`
These line are : `6 to 5, 6 to 4, 6 to 3, 6 to 2, 6 to 1 `(5 lines)
`5 to 4,5 to 3,5 to 2,5 to 1` (4 lines)
`5 to 3, 4 to 2, 4 to 1 `(3 lines)
`3 to 2, 4 to 1` (2 lines)
`2 to 1 ` (1 line)