This new pH of millimolar HCl try …………

Matter 75. (a) step 1 (b) step three (c) dos (d) cuatro Address: (b) step three Service: pH = – log [H + ] [H + ] = ten -3 pH = record step 1 – diary [H + ] = log step 1 – journal ten -3 = step three

Matter 76. These devices of ionic product off liquids K is actually …………… (a) mol -1 L -step one escort Ontario (b) mol -2 L -dos (c) mol -2 L -step 1 (d) mol 2 L -2 Address: (d) mol 2 L -2

Question 77. Review the equilibrium and choose the correct statement. HClO₄ + H₂O \(\rightleftharpoons\) H₃O + + ClO₄ + (a) HClO₄ is the conjugate acid of H₂O (b) H₃O is the conjugate base of H₂O (c) H₂O is the conjugate acid of H₃O (d) ClO₄ is the conjugate base of HCIO₄ Answer: (d) ClO₄ is the conjugate base of HCIO₄

Question 78. Which of the following is the strongest conjugate base? (a) CI – (b) CH₃COO (c) SO₄ 2- (d) NO₂ – Hint: CH₃COO is a conjugate base of a weak acid. CH₃COOH \(\rightleftharpoons\) CH₃COO + H +

Question 79. Which one of the following substance has the highest proton affinity? (a) H₂O (b) H₂S (c) NH₃ (d) PH₃ Answer: (c) NH₃

Question 80. Which of the following is the strongest Lewis acid? (a) BI₃ (b) BBr₃ (c) BCI₃ (d) BF₃ Hint: Larger the size of the halogen atom less is the back donation of electrons into empty 2p orbital of B.

Hence of your own after the is the weakest acid?

Matter 81. (a) HF (b) HCI (c) HBr (d) Hey Respond to: (a) HF Idea: HF will not render proton without difficulty.

Question 82. Among the following, the weakest Lewis base is ………… (a) H – (b) OH – (c) CI – (d) HClO₃ – Hint: CI – is a conjugate base of strong acid HCI.

Question 83. Which of the following is not a Lewis acid? (a) BF₃ (b) AlCI₃ (c) HCl (d) LiAIH₄ Hint: It is a nucleophile and capable of donating electron pair and so it can act as Lewis base.

Matter 84. Which one of adopting the is known as amphoteric solvent? (a) Ammonium hydroxide (b) Chloroform (c) Benzene (d) Drinking water Address: (d) Liquids Clue:

Question 85. Which of the following is non – electrolyte? (a) NaCl (b) CaCl₂ (c) C_{a dozen}H_twenty-twoO₁₁ (d) CH₃COOH Hint: C₁₂H₂₂O₁₁ is a sugar and non-electrolyte.

An acid HA ionises once the HA \(\rightleftharpoons\) H + + Good – The pH of just one

Concern 86. During the infinite dilution, the brand new fee ionisation for both solid and you can weak electrolyte are …………. (a) 1% (b) 20% (c) 50% (d) 100% Answer: (d) 100% Hint: Centered on Ostwald’s dilution law, level of ionisation is really proportional towards dilution.

Concern 87. 0 Yards solution is 5. its dissociation lingering will be ………….. (a) step one x ten -5 (b) 1 x 10 -10 (c) 5 (d) 5 x ten 8 Respond to: (b) 1 x 10 -ten

In which of the above does H₂PO₄ – act as an acid. (a) (i) only (b) (ii) only (c) (i) (iii) (d) (iii) only Answer: (b) (ii) only

Question 89. Which of the following is not a Lewis acid? (a) CO (b) SiCl₄ (c) SO₃ (d) Zn 2+ Answer: (c) SO₃ CO does not contain vacant d-orbital.

Question 90. A chemist dissolves an excess of BaSO₄ in pure water at 25°C if its K_sp = 1 x 10 -10 What is the concentration of Barium in the water? (a) 10 -14 M (b) 10 -5 M (c) 10 -15 M (d) 10 -6 M Answer: (d) 10 -6 M