Incomplete Octet

Q. Which of the following is not hypovalent but complete its octet?

1. $AlC{l}_3$
2. $AlB{r}_3$
3. $B{F}_3$
4. $Al{F}_3$

Q.

Indicate the number of unpaired electrons in P.

Q. Octet rule is not valid for which of the following molecules?

1. $C{O}_2$
2. $N_2$
3. $B{H}_3$
4. $O_2$

Q. The electron deficient compound that has 3c - 2e bond among the following:

1. $B_2{H}_6$
2. $A{l}_{2}C{l}_6$
3. All of the above
4. $BeC{l}_2$ polymer

Q. Find the number of bonded and non bonded electrons in water molecule.

1. $2,4$
2. $4,6$
3. $4,4$
4. $6,4$

Q. Which of the following molecules does not show back bonding?

1. $BC{l}_3$

2. $N(Si{H}_3{)}_3$

3. $CaS{O}_4$

4. $B{F}_3$

Q. The correct statement(s) regarding the binary transition metal carbonyl compounds is (are)
(Atomic numbers: Fe - 26, Ni - 28)

1. Total number of valence shell electrons at metal centre in $Fe\left(CO{)}_{5}orNi\right(CO{)}_4$ is 16
2. These are predominantly low spin in nature
3. Metal - carbon bond strengthens when the oxidation state of the metal is lowered
4. The carbonyl C - O bond weakens when the oxidation state of the metal is increased

Q.

Is Chlorine an Electrophile?

Q.

Which type of electrons are involved in bonding?

1. The innermost electrons
2. Both a) and b)
3. The valence shell electrons
4. None of these

Q. How many $p$ electrons are there in an atom of rubidium (Atomic number: $37$)?

1. $12$
2. $18$
3. $6$
4. $9$

Q. A valid Lewis structure of _____ cannot be drawn without violating the octet rule.

1. $Cl{F}_3$
2. $PC{l}_3$
3. $CC{l}_4$
4. None of these

Q.

In electrovalency:

1. molecules lose electrons, forming atoms

2. molecules gain electrons, forming atoms

3. atoms share electrons

4. atoms lose or gain electrons, forming ions

Q. Predict the correct order of repulsion among the following:

1. $\text{lone pair - lone pair > lone pair - bond pair > bond pair - bond pair}$
2. $\text{lone pair - lone pair > bond pair - bond pair > lone pair - bond pair}$
3. $\text{bond pair - bond pair > lone pair - bond pair > lone pair - lone pair}$
4. $\text{lone pair - bond pair > bond pair - bond pair > lone pair - lone pair}$

Q. Which of the following molecules shows back bonding?

1. $BC{l}_3$
2. $N(Si{H}_3{)}_3$
3. $B{F}_3$
4. All of the above

Q. $LiCl$ and $BC{l}_3$ are examples of .

1. Duplets
2. Incomplete Octet
3. Half-filled Octet

Q. In which of the following molecules is back bonding present?

1. $B{F}_3$
2. $N{H}_3$
3. $H_{2}O$
4. $HF$

Q.

Formula of Freon-11 is-

1. ${\mathrm{CCl}}_3\mathrm{F}$

2. ${\mathrm{CCl}}_2{\mathrm{F}}_2$

3. ${\mathrm{Cl}}_3\mathrm{C}-{\mathrm{CCl}}_2{\mathrm{F}}_2$

4. ${\mathrm{CCl}}_2{\mathrm{FCCl}}_2\mathrm{F}$

Q. The electronic configuration $\left[Kr\right]4d^{10}$ represents ____
($Z$ for$Sr=38$, $Sn=50$, $Te=52$, $Ag=47$)

1. $S{r}^{2+}$
2. $S{n}^{2+}$
3. $A{g}^{+}$
4. $T{e}^{2+}$

Q.

What are electron deficient compounds? Are BCl₃ and SiCl₄ electron deficient species? Explain.

Q. Write hydrocarbon radicals that can be formed as intermediates during monochlorination of $2$-methylpropane? Which of them is more stable? Give reasons.

Q. The number of paired and unpaired electrons in the valence shell of sulphur is:

1. 2, 2
2. 4, 2
3. 2, 4
4. 0, 6

Q. A valid lewis structure of ______ cannot be drawn without violating the octet rule

Q. Which one of the following is/are the incorrect statement(s)?

1. Boric acid is a protonic acid
2. Beryllium exhibits coordination number of six
3. Chlorides of both beryllium and aluminium have bridged chloride structures in solid phase
4. $B_2{H}_6.2N{H}_3$ is known as ‘inorganic benzene’

Q. Hofmann’s Bromamide is used for preparation of amine with one less carbon atom than parent amide.

1. ~
2. ~

Q.

Name the elements which have the following electronic configuration .

(i) 2, 6 (ii) 2, 7 (iii) 2, 8, 1 (iv) 2, 8, 7 (v) 2, 8

Q. An ionic compound AB is most likely to be formed when:

1. The ionisation energy of A is high and electron affinity of B is low
2. The ionisation energy of A is low and electron affinity of B is high
3. Both, the ionisation energy of A and electron affinity of B are high
4. Both, the ionisation energy of A and electron affinity of B are low

Q.

Explain hybridization of {I₃}^-

Q. The pair of elements that form the most ionic compound among the following is:

1. $Na$ and $Cl$
2. $Be$ and $Cl$
3. $B$ and $Si$
4. $Ag$ and $Cl$

Q.

Why are lone pairs important?

Q. Which one of the following is the electron deficient compound?

1. $ICl$
2. $N{H}_3$
3. $BC{l}_3$
4. $PC{l}_3$