What transition in the hydrogen spectrum would have the same wavelength as the Balmer transition, n=4 to n=2 in the He⁺ spectrum?

1. n =4 to n=2

2.  n = 3 to n=2

3.  n =3 to n=1

4.  n =2 to n=1

Which of the following sets of quantum numbers is not possible?

1. n = 1, l=0, m=0, s=1/2

2. n = 2, l=0, m=0, s= -1/2

3. n = 3, l= 3, m = -3, s = 1/2

4. n = 3, l= 1, m = 0, s = -1/2

An isotone of ₃₂Ge⁷⁶ is:

(i) ₃₂Ge⁷⁷ 

(ii) ₃₃As⁷⁷ 

(iii) ₃₄Se⁷⁷ 

(iv) ₃₄Se⁷⁸ 

1. only (i) & (ii)

2. only (ii) & (iii)

3. only (ii) & (iv)

4. (ii) (iii) & (iv)

Which of the following has greater number of electrons than neutrons?

1. Al³⁺

2. O^2-

3. F^-

4. C

The work function of a metal is 4.2 eV. If radiations of 2000 $A^0$ fall on the metal then the kinetic energy of the fastest photoelectron is 

1. 1.6 x 10^-19J 

2. 16 x 10¹⁰J 

3. 3.2 x 10^-19J 

4. 6.4 x 10^-10J 

The relationship between energy E, of the radiation with a wavelength 8000 $A^0$ and the energy of the radiation with a wavelength 16000 $A^0$ is: 

1. E₁ = 6E₂

2. E₁ = 2E₂

3. E₁ = 4E₂

4. E₁ = 1/2E₂

The transition of electrons in H atom that will emit maximum energy is:

1. n₃ $\to$ n₂

2. n₄ $\to$ n₃

3. n₅ $\to$ n₄

4. n₆ $\to$ n₅

The transition in the He⁺ ion in the balmer series that would have the same wave number as the first Lyman line in the hydrogen spectrum is-

If the speed of electron in Bohr's first orbit of hydrogen atom be x, then speed of the electron in 3rd orbit is:

1. x/9

2. x/3

3. 3x

4. 9x

In Bohr's model of the hydrogen atom the ratio between the period of revolution of an electron in the orbit n=1 to the period of revolution of the electron in the orbit n=2 is

1. 1:2

2. 2:1

3. 1:4

4. 1:8