1

### IIT-JEE 1998

ASSERTION:
Nuclide ${}_{13}^{30}Al$ is less stable than ${}_{20}^{40}Ca$

REASON:
Nuclides having odd number of protons and neutrons are generally unstable.
A
If both assertion and reason are correct, and reason is the correct explanation of the assertion.
B
If both assertion and reason are correct, and reason is not the correct explanation of the assertion.
C
If assertion is correct but reason is incorrect.
D
If assertion is incorrect but reason is correct.
2

### IIT-JEE 1998

The orbital diagram in which the Aufbau principle is violated is
A
B
C
D
3

### IIT-JEE 1997

For a d-electron the orbital angular momentum is
A
$\sqrt 6 \left( {h/2\pi } \right)$
B
$\sqrt 2 \left( {h/2\pi } \right)$
C
$\left( {h/2\pi } \right)$
D
$2 \left( {h/2\pi } \right)$
4

### IIT-JEE 1996

The orbital angular momentum of an electron in 2s orbital is
A
$+ {1 \over 2}.{h \over {2\pi }}$
B
Zero
C
${h \over {2\pi }}$
D
$\sqrt 2 .{h \over {2\pi }}$