7s, 7p, 6s, 8p, 8d

Correct Answer: 3

Number of radial nodes is given by the formula:

Radial nodes = n − l − 1

Now calculate for each orbital:

7s : n = 7, l = 0 Radial nodes = 7 − 0 − 1 = 6 ❌

7p : n = 7, l = 1 Radial nodes = 7 − 1 − 1 = 5 ✅

6s : n = 6, l = 0 Radial nodes = 6 − 0 − 1 = 5 ✅

8p : n = 8, l = 1 Radial nodes = 8 − 1 − 1 = 6 ❌

8d : n = 8, l = 2 Radial nodes = 8 − 2 − 1 = 5 ✅

Hence, the atomic orbitals having exactly 5 radial nodes are:

7p, 6s and 8d

Total number of such orbitals = 3