Question

17. Assuming f to be frequency of first line in
Balmer series, the frequency of the immediate
next( ie, second) line is
a) 0.50 / b)1.35 / c)2.05 / d)2.70 /​

Answer 1

Answer:

Frequencies in Lyman series f=RC(1−

n

2

1

)

For series limit of Lyman series: n=∞

∴ f

1

=RC(1−

∞

1

)=RC

For first line of Lyman series : n=2

∴ f

2

=RC(1−

2

2

1

)=0.75RC

Frequencies in Balmer series f=RC(

2

2

1

−

n

2

1

)

For series limit of Balmer series: n=∞

∴ f

3

=RC(

4

1

−

∞

1

)=0.25RC

⟹ f

3

=f

1

−f

2