Which of the following sets consists of isoelectronic species?

1. CO, CN^–, NO⁺, C₂^2–

2. CO^–, CN, NO, C₂^–

3. CO⁺, CN⁺, NO^–, C₂

4. CO, CN, NO, C₂

Which of the following species does not exhibit paramagnetism?

1. N₂⁺

2. O₂^–

3. CO

4. NO

Which of the following pairs contains species that are not isostructural?

1. ${\mathrm{IO}}_3^{-}\text{and\hspace{0.17em}}{\mathrm{XeO}}_3$

2. ${\mathrm{BH}}_4^{-}\text{and\hspace{0.17em}}{\mathrm{NH}}_4^{+}$

3. ${\mathrm{PF}}_6^{-}\text{and\hspace{0.17em}}{\mathrm{SF}}_6$

4. ${\mathrm{SiF}}_4\text{\hspace{0.17em}and\hspace{0.17em}}{\mathrm{SF}}_4$

Identify the correct increasing order of bond length among the following species:

Find the correct reason for H₂O being polar while BeF₂ is non-polar.

In a regular octahedral molecule, MX₆, the number of X–M–X bonds at 180º is:

The dipole moment of compound AB is 10.92 D and that of compound CD is 12.45 D. If the bond length of AB is 2.72 A° and that of CD is 2.56 A°, then for these compounds the correct statement is:

Identify the isoelectronic pair among the following:

In NO₃^– ion, the number of bond pair and lone pair of electrons on nitrogen atom are respectively: