The total number of species from the following in which one unpaired electron is present, is _______.

$\mathrm{N}_2, \mathrm{O}_2, \mathrm{C}_2^{-}, \mathrm{O}_2^{-}, \mathrm{O}_2^{2-}, \mathrm{H}_2^{+}, \mathrm{CN}^{-}, \mathrm{He}_2^{+}$

The oxidation state of manganese in the product obtained in a reaction of potassium permanganate and hydrogen peroxide in basic medium is ____________.

The number of species from the following which have square pyramidal structure is _________

$\mathrm{PF}_{5}, \mathrm{BrF}_{4}^{-}, \mathrm{IF}_{5}, \mathrm{BrF}_{5}, \mathrm{XeOF}_{4}, \mathrm{ICl}_{4}^{-}$

The number of following factors which affect the percent covalent character of the ionic bond is _________

(A) Polarising power of cation

(B) Extent of distortion of anion

(C) Polarisability of the anion

(D) Polarising power of anion

In alanylglycyl leucyl alanyl valine, the number of peptide linkages is ___________.

The number of species from the following which are paramagnetic and with bond order equal to one is _________.

$\mathrm{H}_2, \mathrm{He}_2^{+}, \mathrm{O}_2^{+}, \mathrm{N}_2^{2-}, \mathrm{O}_2^{2-}, \mathrm{F}_2, \mathrm{Ne}_2^{+}, \mathrm{B}_2$

The number of molecules or ions from the following, which do not have odd number of electrons are _________.

(A) NO$_2$

(B) ICl$_4^ -$

A set of 20 tuning forks is arranged in a series of increasing frequencies. If each fork gives 4 beats with respect to the preceding fork and the frequency of the last fork is twice the frequency of the first, then the frequency of last fork is _________ Hz.

Number of molecules having bond order 2 from the following molecules is _________.

$\mathrm{C}_2, \mathrm{O}_2, \mathrm{Be}_2, \mathrm{Li}_2, \mathrm{Ne}_2, \mathrm{~N}_2, \mathrm{He}_2$

The total number of molecular orbitals formed from $2 \mathrm{s}$ and $2 \mathrm{p}$ atomic orbitals of a diatomic molecule is __________.

A box contains 0.90 g of liquid water in equilibrium with water vapour at 27$^\circ$C. The equilibrium vapour pressure of water at 27$^\circ$C is 32.0 Torr. When the volume of the box is increased, some of the liquid water evaporates to maintain the equilibrium pressure. If all the liquid water evaporates, then the volume of the box must be __________ litre. [nearest integer]