Which of these can not be a Bronsted acid?

1. ${\mathrm{HCO}}_3^{-}$

2. ${\mathrm{HCOO}}^{-}$

3. ${\mathrm{H}}_2{\mathrm{PO}}_3^{-}$

4. ${\mathrm{H}}_3{\mathrm{O}}^{+}$

In \(HS^-, I^-, RNH_2, \ and\ NH_3\) the order of proton-accepting tendency will be:

1. ${\mathrm{I}}^{-}>{\mathrm{NH}}_3>{\mathrm{RNH}}_2>{\mathrm{HS}}^{-}$

2. ${\mathrm{HS}}^{-}>{\mathrm{RNH}}_2>{\mathrm{NH}}_3>{\mathrm{I}}^{-}$

3. ${\mathrm{RNH}}_2>{\mathrm{NH}}_3>{\mathrm{HS}}^{-}>{\mathrm{I}}^{-}$

4. ${\mathrm{NH}}_3>{\mathrm{RNH}}_2>{\mathrm{HS}}^{-}>{\mathrm{I}}^{-}$

Which one of the following orders of acid strength is correct?

1. $\mathrm{RCOOH}>\mathrm{HC}\equiv \mathrm{CH}>\mathrm{HOH}>\mathrm{ROH}$

2. $\mathrm{RCOOH}>\mathrm{ROH}>\mathrm{HOH}>\mathrm{HC}\equiv \mathrm{CH}$

3. $\mathrm{RCOOH}>\mathrm{HOH}>\mathrm{ROH}>\mathrm{HC}\equiv \mathrm{CH}$

4. $\mathrm{RCOOH}>\mathrm{HOH}>\mathrm{HC}\equiv \mathrm{CH}>\mathrm{ROH}$

A centinormal solution of a monobasic acid is 100% ionized. Its pH is:

1. 2

2. 4

3. 3

4. 1

Find the mixture that can act as a buffer solution.

Which one of the following statements is not correct?

At \(90^\circ \text C,\) pure water has \([H_3O^+]=10^{-6}~\text{mole litre}^{-1}.\) What is the value of \(K_w\) at \(90^\circ \text C?\)

Which of the following anions is the strongest Brønsted base?

1. ${\mathrm{ClO}}_4^{-}$

2. ${\mathrm{ClO}}_3^{-}$

3. ${\mathrm{ClO}}_2^{-}$

4. ${\mathrm{ClO}}^{-}$

What is the pH of a 10⁻⁸ M solution of HCl in water?

1. -8

2. 8

3. between 6 and 7

4. between 7 and 8

Find the pair of solutions that can be mixed to prepare an acidic buffer.

1. Sodium chloride and sodium hydroxide

2. Sulphuric acid and sodium sulphate

3. Ammonium chloride and ammonium nitrate

4. Ammonium acetate and acetic acid