Arrhenius Acid

Q. Among the following acids which has the lowest $p{K}_a$ value?

1. $C{H}_{3}COOH$
2. $HCOOH$
3. $(C{H}_3{)}_{2}CHCOOH$
4. $C{H}_{3}C{H}_{2}COOH$

Q. When 9.45 g of $ClC{H}_{2}COOH$ is added to 500 mL of water , its freezing point drops by ${0.5}^{0}C$ . The dissociation constant of $ClC{H}_{2}COOH$ is $x\times {10}^{-3}$ . The value of x is ( Rounded off to the nearest integer )
$[K_{f\left(H_{2}O\right)}=1.86Kgmo{l}^{-1}]$

Q.

Define the degree of ionization or dissociation?

Q.

Give the advantages and disadvantages of potentiometric titration.

Q.

How is the concentration of hydronium ions affected when a solution of an acid is diluted?

Q.

Value of dissociation constant of acetic acid is ${10}^{-6}$, where as dissociation constant of formic acid is ${10}^{-5}$. Which of the following will be the value of pK${}_a$(acetic acid) - pK${}_a$(formic acid)
a)10
b)1
c)${10}^{-1}$
d)-1

Q.

What is the Principle of Limit Test for Chloride?

Q.

Which among the following is a Lewis acid?

1. ${\mathrm{NH}}_3$

2. ${\mathrm{NH}}_4^{+}$

3. ${\mathrm{BF}}_3$

4. ${\mathrm{H}}_2\mathrm{O}$

Q.

Is $\mathrm{OH}$ group electron donating or withdrawing?

Q.

Why does ${\mathrm{BF}}_3$ act as a Lewis acid ?

Q.

The correct way of making a solution of acid in water is to

1. add water to acid.

2. add acid to water.

3. mix acid and water simultaneously.

4. add water to acid in a shallow container.

Q.

Why are amino acids amphoteric?

Q.

Circle the odd one out

1. NaOH

2. HCl

3. HNO₃

4. H₂SO₄

Q.

Why limiting molar conductivity of ${\mathrm{CH}}_3\mathrm{COOH}$ cannot be determined experimentally?

Q.

Which of the following substances gives a positively charged sol?

1. Gold

2. Arsenious sulfide

3. Starch

4. Ferric hydroxide

Q.

Which Of The Following Is The Conjugate Acid Of ${\mathrm{SO}}_4^{2-}$?

1. ${\mathrm{H}}^{+}$

2. ${\mathrm{SO}}_4^{2-}$

3. ${\mathrm{HSO}}_4^{-}$

4. ${\mathrm{H}}_2{\mathrm{SO}}_4$

Q. Ionisation enthalpy of an atom is equal to :-
1. Electron gain enthalpy of the cation.
2. Electronegativity of the ion.
3. Ionisation enthalpy of the cation.
4. Electron gain enthalpy of anion.

Q.

What is ${\mathrm{K}}_{\mathrm{a}}$ in chemistry?

Q.

What is deprotonation?

Q.

In a ______________ reaction two or more substances combine to form a new single substance.

Q.

A white crystal compound N when warmed with concentrated sulphuric acid gives a gas that turns fumes into ammonia. When N is warmed with sodium hydroxide solution gas is evolved which turns moist red litmus paper blue.

Identify the solid N and name the two gases that evolved in each case.

Q. Which of the following cannot act as Lewis acid?

1. 
2. 
3. 
4. 

Q. Consider the following statements : (i) With increase in dilution, molar conductance of a weak electrolyte solution increases whereas specific conductance decreases due to decrease in interionic attractions (ii) ∧m∞ for AgCl can be determined by extrapolation of the graph between ∧m and C (iii) For weak electrolytes, ∧m or ∧eq increases rapidly with dilution in the lower concentration range. Choose the correct statement (s) (1) I, II, III (2) only III (3) I, II (4) II, III

Q.

State a safety precaution that you should take during the preparation of hydrochloric acid.

Q.

Two elements whose electronegativities are 1.2 and 3.0 the bond formed between them would be

1. Covalent

2. Ionic

3. Metallic

4. Coordinate

Q. Which of the following cannot undergo hydrolysis:

1. 
2. 
3. 
4. 

Q.

What is a combination reaction?

Q. 18 In the electrolysis of aqueous solution of NaOH, 2.8 L of O2 at NTP was liberated at the anode . how much H2 was liberated at cathode?

Q.

Assertion $\left(A\right):$ Increasing order of acidity of hydrogen halides is

$HF<HCl<HBr<HI$

Reason $\left(R\right):$ While comparing acids formed by the elements belonging to the same group of periodic table

$H-A$ bond strength is a more important factor in determining acidity of an acid than the polar nature of the bond.

1. $A$ is true but $R$ is false.

2. $A$ is false but $R$ is true.

3. Both $A$ and $R$ are true and $R$ is the correct explanation of $A.$

4. Both $A$ and $R$ are true but $R$ is not the correct explanation of $A.$

Q. Q3-1, 3, 5 trihydroxy benzene on reaction with HCN+HCL and ZnCl2 +H2O gives?