Question

The correct statement about probability density (except at infinite distance from nucleus) is

• A. It can never be zero for 2s orbital
• B. It can be zero for 3p orbital
• C. It can be zero for 1s orbital
• D. It can be negative for 2p orbital

Answer 1

The correct option is B It can be zero for 3p orbital



Probability density is the square of wave function and hence is always positive . So, option d is wrong.
Probality density changes with distance (radius) from nucleus. It becomes zero at radial nodes.

In 1s graph, the probability density curve does not become zero at any distance hence, option (c) is wrong.

In 2s graph, the probability density curve becomes zero at a point which is know as node. Hence, potion (a) is wrong.

In 3p graph, we have a minimum curve which denotes the node where probability density is zero.
Hence, option (b) is the correct statement.