acids and bases

Which of the following is/are formed when a metal oxide reacts with a dilute acid?

I. A metal salt

II. Water

III. Hydrogen gas

• A. I only

• B. I and II only

• C. II and III only

• D. I, II and III

Which equation represents an acid-base reaction according to the Lewis theory but not according to the Brønsted-Lowry theory?

• CO32–(aq) + 2H+(aq) → H2O(l) + CO2(g)

• Cu2+(aq) + 4NH3(aq) → CU(NH3)42+(aq)

• BaO(s) + H2O(l) → Ba2+(aq) + 2OH–(aq)

• NH3(g) + HCl(g) → NH4Cl(s)

Which equation represents an acid-base reaction according to the Lewis theory but not the Brønsted-Lowry theory?

• NH3 + HCl NH4Cl

• 2H2O H3O+ + OH–

• NaOH + HCl NaCl + H2O

• CrCl3 + 6NH3 [Cr(NH3)6]3+ + 3Cl–

Which is a buffer solution?

I. 0.01 mol dm–3 HCl, 0.01 mol dm–3 NaCl

II. 0.01 mol dm–3 CH3COOH, 0.01 mol dm–3 CH3COONa

• A. I only

• B. II only

• C. Both I and II

• D. Neither I nor II

Which substance can be dissolved in water to give a 0.1 mol dm–3 solution with a high pH and a high electrical conductivity?

• HCl

• NaCl

• NH3

• NaOH

What is the concentration of OH– ions (in mol dm–3) in an aqueous solution in which [H+] = 2.0×10–3 mol dm–3? (Kw = 1.0×10–14 mol2 dm–6)

• 2.0×10–3

• 4.0×10–6

• 5.0×10–12

• 2.0×10–17

Which is not a strong acid?

• Nitric acid

• Sulfuric acid

• Carbonic acid

• Hydrochloric acid

What is the conjugate base of the HSO4–(aq) ion?

• H2SO4(aq)

• SO42–(aq)

• H2O(l)

• H3O+(aq)

Solutions of hydrochloric acid (HCl(aq)) and ethanoic acid (CH3COOH(aq)) of the same concentration reacted completely with 5.0 g of calcium carbonate in separate containers. Which statement is correct?

• CH3COOH(aq) reacted slower because it has a lower pH than HCl(aq).

• A smaller volume of CO2(g) was produced with CH3COOH(aq) than with HCl(aq).

• A greater volume of CO2(g) was produced with CH3COOH(aq) than with HCl(aq).

• The same volume of CO2(g) was produced with both CH3COOH(aq) and HCl(aq).

What pH is the strongest base?

• 1

• 7

• 4

• 14