Isostructural species are those which have the same shape and hybridisation. Among the given species identify the isostructural pairs.
Polarity in a molecule and hence the dipole moment depends primarily on electronegativity of the constituent atoms and shape of a molecule. Which of the following has the highest dipole moment?
The types of hybrid orbitals of nitrogen in $\mathrm{NO}_2^{+}, \mathrm{NO}_3^{-}$and $\mathrm{NH}_4^{+}$ respectively are expected to be
Hydrogen bonds are formed in many compounds e.g., $\mathrm{H}_2 \mathrm{O}, \mathrm{HF}, \mathrm{NH}_3$. The boiling point of such compounds depends to a extent on the strength of hydrogen bond and the number of hydrogen bonds. The correct decreasing order of the boiling points above compounds is
In $\mathrm{PO}_4^{3-}$ ion the formal charge on the oxygen atom of $\mathrm{P}-0$ bond is
In $\mathrm{NO}_3^{-}$ion, the number of bond pairs and lone pairs of electrons on nitrogen atom are
Which of the following species has tetrahedral geometry?
Number of $$\pi$$ bonds and $$\sigma$$ bonds in the following structure is
Which molecule/ion out of the following does not contain unpaired electrons?
In which of the following molecule/ion all the bonds are not equal?
In which of the following substances will hydrogen bond be strongest?
If the electronic configuration of an element is $1 s^2 2 s^2 2 p^6 3 s^2 3 p^6 3 d^2 4 s^2$, the four electrons involved in chemical bond formation will be
Which of the following angle corresponds to sp$$^2$$ hybridisation?
Stable form of $A$ may be represented by the formula
Stable form of $C$ may be represented by the formula
The molecular formula of the compound formed from $B$ and $C$ will be
The bond between $B$ and $C$ will be
Which of the following order of energies of molecular orbitals of $\mathrm{N}_2$ is correct?
Which of the following statement is not correct from the view point of molecular orbital theory?
Which of the following options represents the correct bond order?
The electronic configuration of the outer most shell of the most electronegative elements is
Amongst the following elements whose electronic configuration are given below, the one having the highest ionisation enthalpy is
Assertion (A) Sodium chloride formed by the action of chlorine gas on sodium metal is a stable compound.
Reason (R) This is because sodium and chloride ions acquire octet in sodium chloride formation.
Assertion (A) Though the central atom of both $\mathrm{NH}_3$ and $\mathrm{H}_2 \mathrm{O}$ molecules are $s p^3$ hybridised, yet $\mathrm{H}-\mathrm{N}-\mathrm{H}$ bond angle is greater than that of $\mathrm{H}-\mathrm{O}-\mathrm{H}$.
Reason (R) This is because nitrogen atom has one lone pair and oxygen atom has two lone pairs.
Assertion (A) Among the two $0-\mathrm{H}$ bonds in $\mathrm{H}_2 \mathrm{O}$ molecule, the energy required to break the first $0-\mathrm{H}$ bond and the other $0-\mathrm{H}$ bond is the same.
Reason (R) This is because the electronic environment around oxygen is the same even after breakage of one $0-\mathrm{H}$ bond.
Which of the following statements is correct?
Which of the following molecular orbitals has maximum number of nodal planes?
Which of the following pair is expected to have the same bond order?
In which of the following molecules, $\sigma 2 p_z$ molecular orbital is filled after $\pi 2 p_x$ and $\pi 2 p_y$ molecular orbitals?
Which of the following have identical bond order?
Which of the following attain the linear structure?
CO is isoelectronic with
Which of the following species have the same shape?
Which of the following statements are correct about $\mathrm{CO}_3^{2-}$ ?
Diamagnetic species are those which contain no unpaired electrons. Which among the following are diamagnetic?
Species having same bond order are
Which of the following statements are not correct?
Explain the non-linear shape of $\mathrm{H}_2 \mathrm{~S}$ and non-planar shape of $\mathrm{PCl}_3$ using valence shell electron pair repulsion theory.
Using molecular orbital theory, compare the bond energy and magnetic character of $\mathrm{O}_2^{+}$and $\mathrm{O}_2^{-}$species.
Explain the shape of BrF$$_5$$.
Structures of molecules of two compounds are given below.
(a) Which of the two compounds will have intermolecular hydrogen bonding and which compound is expected to show intramolecular hydrogen bonding?
(b) The melting point of compound depends on, among other things, the extent of hydrogen bonding. On this basis explain which of the above two compounds will show higher melting point?
(c) Solubility of compounds in water depends on power to form hydrogen bonds with water. Which of the above compounds will form hydrogen bond with easily and be more soluble in it?
Why does type of overlap given in the following figure not result in bond formation?
Explain why $\mathrm{PCl}_5$ is trigonal bipyramidal whereas $\mathrm{IF}_5$ is square pyramidal.
In both water and dimethyl ether 
, oxygen atom is central atom, and has the same hybridisation, yet they have different bond angles. Which one has greater bond angle? Give reason.
Write Lewis structure of the following compounds and show formal charge on each atom.
$$\mathrm{HNO}_3, \mathrm{NO}_2, \mathrm{H}_2 \mathrm{SO}_4$$
The energy of $\sigma 2 p_z$ molecular orbital is greater than $\pi 2 p_x$ and $\pi 2 p_y$ molecular orbitals in nitrogen molecule. Write the complete sequence of energy levels in the increasing order of energy in the molecule. Compare the relative stability and the magnetic behaviour of the following species.
$$\mathrm{N}_2, \mathrm{~N}_2^{+}, \mathrm{N}_2^{-}, \mathrm{N}_2^{2+}$$
What is the effect of the following processes on the bond order in $\mathrm{N}_2$ and $\mathrm{O}_2$ ?
(a) $\mathrm{N}_2 \longrightarrow \mathrm{N}_2^{+}+e^{-}$
(b) $\mathrm{O}_2 \longrightarrow \mathrm{O}_2^{+}+e^{-}$
Give reason for the following.
(a) Covalent bonds are directional bonds while ionic bonds are non-directional.
(b) Water molecule has bent structure whereas carbon dioxide molecule is linear.
(c) Ethyne molecule is linear.
What is an ionic bond? With two suitable examples the difference between an ionic and a covalent bond?
Arrange the following bonds in order of increasing ionic character giving reason.
$$\mathrm{N}-\mathrm{H}, \quad \mathrm{F}-\mathrm{H}, \quad \mathrm{C}-\mathrm{H} \text { and } \mathrm{O}-\mathrm{H}$$
Explain why $\mathrm{CO}_3^{2-}$ ion cannot be represented by a single Lewis structure. How can it be best represented?
Predict the hybridisation of each carbon in the molecule of organic compound given below. Also indicate the total number of sigma and pi-bonds in this molecule.
Group the following as linear and non-linear molecules.
$$\mathrm{H}_2 \mathrm{O}, \mathrm{HOCl}, \mathrm{BeCl}_2, \mathrm{Cl}_2 \mathrm{O}$$
Elements $X, Y$ and $Z$ have 4, 5 and 7 valence electrons respectively.
(a) Write the molecular formula of the compounds formed by these elements individually with hydrogen.
(b) Which of these compounds will have the highest dipole moment?
Draw the resonating structure of
(a) ozone molecule
(b) nitrate ion
Predict the shapes of the following molecules on the basis of hybridisation.
$$\mathrm{BCl}_3, \mathrm{CH}_4, \mathrm{CO}_2, \mathrm{NH}_3$$
All the $\mathrm{C}-0$ bonds in carbonate ion $\left(\mathrm{CO}_3^{2-}\right)$ are equal in length. Explain.
What is meant by the term average bond enthalpy? Why is there difference in bond enthalpy of 0-H bond in ethanol $\left(\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}\right)$ and water?
Match the species in Column I with the type of hybrid orbitals in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | SF$$_4$$ | 1. | sp$$^3$$d$$^2$$ |
| B. | IF$$_5$$ | 2. | d$$^2$$sp$$^3$$ |
| C. | NO$$_2^+$$ | 3. | sp$$^3d$$ |
| D. | NH$$_4^+$$ | 4. | sp$$^3$$ |
| 5. | sp |
Match the species in Column I with the geometry/shape in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | $$ \mathrm{H}_3 \mathrm{O}^{+} $$ |
1. | Linear |
| B. | $$ \mathrm{HC} \equiv \mathrm{CH} $$ |
2. | Angular |
| C. | $$ \mathrm{ClO}_2^{-} $$ |
3. | Tetrahedral |
| D. | NH$$_4^+$$ | 4. | Trigonal bipyramidal |
| 5. | Pyramidal |
Match the species in Column I with the bond order in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | NO | 1. | 1.5 |
| B. | CO | 2. | 2.0 |
| C. | O$$_2^-$$ | 3. | 2.5 |
| D. | O$$_2$$ | 4. | 3.0 |
Match the items given in Column I with examples given in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | Hydrogen bond | 1. | C |
| B. | Resonance | 2. | LiF |
| C. | Ionic solid | 3. | H$$_2$$ |
| D. | Covalent solid | 4. | HF |
| 5. | O$$_3$$ |
Match the shape of molecules in Column I with the type of hybridisation in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | Tetrahedral | 1. | sp$$^2$$ |
| B. | Trigonal | 2. | sp |
| D. | Linear | 4. | sp$$^3$$ |
(a) Discuss the significance/applications of dipole moment.
(b) Represent diagrammatically the bond moments and the resultant dipole moment in $\mathrm{CO}_2, \mathrm{NF}_3$ and $\mathrm{CHCl}_3$.
Use the molecular orbital energy level diagram to show that $\mathrm{N}_2$ would be expected to have a triple bond. $\mathrm{F}_2$, a single bond and $\mathrm{Ne}_2$, no bond.
Briefly describe the valence bond theory of covalent bond formation by taking an example of hydrogen. How can you interpret energy changes taking place in the formation of dihydrogen?
Describe hybridisation in the case of $\mathrm{PCl}_5$ and $\mathrm{SF}_6$. The axial bonds are longer as compared to equatorial bonds in $\mathrm{PCl}_5$ whereas in $\mathrm{SF}_6$ both axial bonds and equatorial bonds have the same bond length. Explain.
(a) Discuss the concept of hybridisation. What are its different types in a carbon atom?
(b) What is the type of hybridisation of carbon atoms marked with star?
