A. For 1s orbital, the probability density is maximum at the nucleus.

B. For 2s orbital, the probability density first increases to maximum and then decreases sharply to zero.

C. Boundary surface diagrams of the orbitals encloses a region of 100% probability of finding the electron.

D. p and d-orbitals have 1 and 2 angular nodes respectively.

E. Probability density of p-orbital is zero at the nucleus.

Correct Answer: 3

Statement A is correct because 1s orbital has maximum probability density at the nucleus.

Statement B is incorrect because 2s orbital has one radial node; probability density decreases to zero and then increases again before finally decreasing.

Statement C is incorrect because boundary surface diagrams enclose about 90–95% probability, not 100%.

Statement D is correct as p-orbitals have 1 angular node and d-orbitals have 2 angular nodes.

Statement E is correct because probability density of p-orbital at the nucleus is zero.

Hence, total correct statements = 3.