Percentage of free space in a body centre cubic unit cell is:

1. 30%

2. 32%

3. 34%

4. 28%

For the reaction, N2 (g) +O2 (g) 2NO (g), the equilibrium constant is k1. The equilibrium constant is K2 for the reaction, 2NO (g) +O2 (g) 2NO2 (g). What is k for the reaction, NO2 (g) N2?

1. $1/\left(4K_1{K}_2\right)$

2. $[1/K_1{K}_2{]}^{1/2}$

3. $11\left(K_1{K}_2\right)$

4. $11\left(2K_1{K}_2\right)$

Acidified K₂Cr₂O₇ solution turns green when Na₂SO₃ is added to it. This is due to the formation of:

1. $Cr{O}^{-}$

2. $C{r}_2{\left(S{0}_3\right)}_3$

3. $CrS{O}_4$

4. $C{r}_2{\left(S{O}_4\right)}_3$

Among the following the least thermally stable is:

1. $K_{2}C{O}_3$

2. $N{a}_{2}C{O}_3$

3. $BaC{O}_3$

4. $L{i}_{2}C{O}_3$

Which one of the following is 'd' block element?

1. Gd

2. Hs

3. Es

4. Cs

The angular shape of ozone molecule (0₃) consists of:

1. 1 sigma and 2 pi bonds

2. 2 sigma and 2 pi bonds

3. 1 sigma and 1 pi bonds

4. 2 sigma and 1 pi bonds

If the E⁰_cell for a given reaction has a negative value then which of the following gives the correct relationships for the values of G⁰ and K_eq?

1. $∆G^{°}<0; k_{eq}>1$

2. $∆G^{°}<0; k_{eq}<1$

3. $∆G^{°}>0; k_{eq}<1$

4. $∆G^{°}<0; k_{eq}<1$

Among the following the molecule possessing highest dipole moment is:

1. $C{O}_2$

2. $B{F}_3$

3. $S{O}_2$

4. Trans-2-butene

An electron is moving in Bohr's fourth orbit. Its de-Broglie wavelength is λ. What is the circumference of the fourth orbit?

1. $\frac{2}{\lambda }$

2. $2\lambda$

3. $4\lambda$

4. $\frac{4}{\lambda }$

The standard enthalpies of formation of A (NH₃), B (CO₂), C (HI) and D (SO₂) are - 46.19, -393.4, +24.94 and -296.9 kJ mol^-1 respectively. The increasing order of their stability is:

1. B < D < A <C

2.  C < A < D <B

3.  D < B < C <A

4.  A < C < D <B