Lewis Theory

Q.

What is the Hard Acid Soft Base Theory?

Q.

What is spectrochemical series? Explain the difference between a weak field ligand and a strong field ligand.

Q.

Which of the followings are Lewis acids? $H_{2}O,B{F}_3,H^{+}$, and $N{H}_4^{+}$

Q.

Choose the correct order of the basic nature of the below-given amines.

A. Phenyl methenamine

B.$\mathrm{N}-\mathrm{N}$-Dimethylaniline

C. $\mathrm{N}$-Methyl aniline

D. Benzenamine

1. $\mathrm{D}>\mathrm{C}>\mathrm{B}>\mathrm{A}$

2. $\mathrm{D}>\mathrm{B}>\mathrm{C}>\mathrm{A}$

3. $\mathrm{A}>\mathrm{C}>\mathrm{B}>\mathrm{D}$

4. $\mathrm{A}>\mathrm{B}>\mathrm{C}>\mathrm{D}$

Q.

Write the formula for Hydrochloric acid.

Q.

What is the difference between ionization and dissociation?

Q.

Name the strongest acid in the world.

Q. Calculate the pH at the equivalence point during the titration of 0.1 M, 25 ml $C{H}_3$ COOH with 0.05 M NaOH solution $k_a$ $\left(C{H}_{3}COOH\right)=1.8\times {10}^{-5}$

1. 8.63
2. 10.63
3. 11.63
4. 9.63

Q.

Classify the following species into Lewis acids and Lewis bases and show how these act as Lewis acid/base:
(a) $O{H}^{–}$
(b) $F^{–}$
(c) $H^{+}$
(d) $BC{l}_3.$

Q. Boron compounds behave as Lewis acids because of their :

1. acidic nature
2. ionic nature
3. covalet nature
4. vacant orbital

Q. Acidic strength of an acid is

1. directly propotional to strength of EWG
2. inversly propotional to strength of EWG
3. inversly propotional to strength of conjugate acid
4. directly proptional to strength of conjugate base

Q.

Protonic acid is

Q.

Which is more acidic Toluene or Phenol?

Q. Molarity of a mixture of acid and base

Q. Which of the following species is not a Lewis acid?

1. $B{F}_3$
2. $C{u}^{2+}$
3. $N{H}_3$
4. $AlC{l}_3$

Q. Which of the following is lewis acid?

1. $N{H}_3$
2. $AlC{l}_3$
3. $P{H}_3$
4. None of the above

Q.

Are all nucleophiles bases ?

Q. find Ph of a solution when 100 ml of 0.1 N hcl is mixed with 100 ml of 0.1 M nh4oh solution ( pka (nh4+)=9.3) a)4.65 b)7 c)8.7 d)5.3

Q. The $K_a$ of an acid is 3.2 $\times$ ${10}^{–5}$. The degree of dissociation of the acid at concentration of 0.2 M is

1. $1.26\times {10}^{-2}$
2. $40\times {10}^{-4}$
3. $0.04\times {10}^{-3}$
4. $6.0\times {10}^{-2}$

Q.

Are all bases nucleophiles?

Q. Which of the following is not a Lewis acid ?

1. $N{H}_3$
2. $SiC{l}_4$
3. $S{O}_3$
4. $Z{n}^{2+}$

Q. A base is a substance which

1. (a) and (b) above.
2. None of the above
3. donate a lone pair of electron(Lewis concept)
4. accepts a proton ( Lowry and Bronsted concept)

Q.

What is the conjugate base of ${\text{HCO}}_3^{-}$ and ${\mathrm{H}}_2\mathrm{O}$?

Q. Which of the following is not Lewis acid?

1. $AlC{l}_3\cdot 6H_{2}O$
2. $AlC{l}_3$
3. $BC{l}_3$
4. All of these

Q.

A solution X turns blue litmus red and another solution Y turns red litmus blue, when solutions X and Y are mixed the products will be ___ and ___, if a piece of magnesium were put into solution X___ gas, would be evolved.

Q.

Electrophiles are

1. Bronsted acid

2. Lewis acids

3. Bronsted base

4. Lewis base

Q. The total number of lone pairs present in XeF4 is
A) 10
B) 12
C) 14
D) 16

I did not understand the question because I know that there are only 2 lone pairs in XeF4. Can I please get the answer with an explanatation.
Thank you

Q. The compound that is not a Lewis acid is:

1. $B{F}_3$
2. $AlC{l}_3$
3. $BeC{l}_2$
4. $N{H}_3$

Q.

Which of the following is not a hydra acid?

1. $\mathrm{HCl}$

2. ${\mathrm{H}}_2\mathrm{S}$

3. ${\mathrm{H}}_2{\mathrm{SO}}_3$

4. $\mathrm{HBr}$

Q. Which of the following is most likely to behave as a lewis base?

1. $B{F}_3$
2. $P{F}_3$
3. $C{F}_3$
4. $Si{F}_4$