Question

Arrange in order of the increasing vacuum work function for the below-mentioned metals:

a) Au

b) Ni

c) Ag

d) Al

Which of the following options is correct?

1. d, c, b, a
2. c, d, a, b
3. b, a, c, d
4. a, b, d, c

Answer 1

Correct Answer - Option 1 : d, c, b, a

Concept:

Work function

It is defined as the minimum amount of the energy of the incident photon required to release the electron from the metal surface.

It is different for different metals and it depends on the

• Nature of the metal
• Impurities present on its surface

Work functions of the given metals are shown below:

Metal	Work function
Au	5.10 – 5.47
Ni	5.04 – 5.35
Ag	4.26 – 4.74
Al	4.06 – 4.26

 

The increasing order of the work function is Al < Ag < Ni < Au i.e., d < c < b < a