Cathode rays are deflected by _______.

1

(a)

electric field only

(b)

electric and magnetic field

(c)

magnetic field only

(d)

none of these

The Balmer series in the spectrum of hydrogen atom falls in _______.

1

(a)

ultraviolet region

(b)

visible region

(c)

infrared region

(d)

none of these

The energy needed to remove a single electron (most loosely bound) from an isolated gaseous atom is called _______.

1

(a)

ionisation energy

(b)

electronegativity

(c)

kinetic energy

(d)

electron affinity

The maximum number of electrons in a sub-shell is given by the equation _______.

1

(a)

n²

(b)

2n²

(c)

21-1

(d)

21 + 1

If the value of azimuthal quantum number is 2, what will be the values for magnetic quantum number?

1

(a)

2

(b)

3

(c)

4

(d)

5

What is the difference in the origin of cathode rays and anode rays?

1

(a)

Cathode rays originate from the cathode whereas anode rays are not obtained from the anode. They are produced from the gaseous atoms by knock out of the electrone with high speed cathode rays

Why are Bohr's orbits called stationary states?

1

(a)

This is because the energies of the orbits in which the electrons revolve are fixed.

Which of the following orbitals are degenerate?

1

(a)

The orbitals which belong to same subshell and same shell are called degenerate orbitals.\({ (3d }_{ xy },{ 3d }_{ { z }^{ 2 } },{ 3d }_{ yz })\) and \(({ 4 \ d }_{ xy },{ 4 \ d }_{ zy },{ 4 \ d }_{ { z }^{ 2 } })\) are the two sets of degenerate orbitals.

Which series of lines of the hydrogen spectrum lie in the visible region?

1

(a)

Balmer series.

Which one Fe³⁺, Fe²⁺ is more paramagnetic and why?

1

(a)

As Fe³⁺ contains 5 unpaired electrons while Fe²⁺ contains only 4 unpaired electrons. Fe³⁺ is more paramagnetic.

What is the difference between ground state and excited state?

1

(a)

Ground state means the lowest energy state. When the electrons absorb energy and jump to outer orbits, this state is called excited state.

Show the distribution of electrons in oxygen atom (atomic number 8) using an orbital diagram.

1

(a)

₈O = 1 s² 2s²  2p⁴