AP Chemistry Exam Multiple Choice Questions

1.	50 cm3 of 0.2 N HCI is titrated against 0.1 N NaOH solution. The titration is discontinued after adding 50 cm3 of NaOH. The remaining titration is completed by adding 0.5 N KOH. The volume of KOH required for completing the titration is ______. (A) 10 cm3 (B) 12 cm3 (C) 10.5 cm3 (D) 25 cm3	Answer: (A)
2.	80 g of oxygen contains as many atoms as in (A) 80 g of hydrogen (B) 1 g of hydrogen (C) 10 g of hydrogen (D) 5 g of hydrogen	Answer: (D)
3.	9.65 C of electric current is passed through fused anhydrous magnesium chloride. The magnesium metal thus obtained is completely converted into a Grignard reagent. The number of moles of the Grignard reagent obtained is ______. (A) 1 ´ 10-4 (B) 5 ´ 10-4 (C) 1 ´ 10-5 (D) 5 ´ 10-5	Answer: (D)
4.	A 6% solution of urea is isotonic with (A) 6% solution of Glucose (B) 25% solution of Glucose (C) 1 M solution of Glucose (D) 0.05 M solution of Glucose	Answer: (C)
5.	A bivalent metal has an equivalent mass of 32. The molecular mass of the metal nitrate is (A) I92 (B) 188 (C) 182 (D) 168	Answer: (B)
6.	A body of mass 10 mg is moving with a velocity of 100 ms-1. The wavelength of de-Broglie wave associated with it would be (Note : h = 6.63 ´ 10-34Js) (A) 6.63 ´ 10-37m (B) 6.63 ´ 10-31m (C) 6.63 ´ 10-34m (D) 6.63 ´ 10-35m	Answer: (B)
7.	A body of mass x kg is moving with a velocity of 100 ms-1. Its de Broglie wavelength is 6.62 ´ 10-35m. Hence x is (h = 6.62 ´ 10-34Js) (A) 0.15 kg (B) 0.2 kg (C) 0.1 kg (D) 0.25 kg	Answer: (C)
8.	A buffer solution contains 0.1 mole of sodium acetate dissolved in 1000 cm3 of 0.1 M acetic acid. To the above buffer solution, 0.1 mole of sodium acetate is further added and dissolved. The pH of the resulting buffer is equal to ______. (A) pKa (B) pKa - Log2 (C) pKa + L0g2 (D) pKa + 2	Answer: (C)
9	A buffer solution is prepared in which the concentration of NH3 is 0.30 M and the concentration of  is 0.20 M. If the equilibrium constant, Kb for NH3 equals 1.8 × 10–5, what is the pH of this solution? (A) 8.73 (B) 9.08 (C) 9.43 (D) 11.72	Answer: (C)
10.	A complex compound in which the oxidation number of a metal is zero is (A) K4 [Fe (CN)6] (B) K3 [Fe (CN)6] (C) [Ni (CO)4] (D) [Pl (NH3 )4]Cl2	Answer: (C)
11.	Which of the following is used to prepare Cl2 gas at room temperature from concentrated HCI? (A) MnO2 (B) H2S (C) KMnO4 (D) Cr2O3	Answer: (C)
12.	Which of the following is not an ore of magnesium? (A) Carnallite (B) Dolomite (C) Calamine (D) Sea water	Answer: (C)
13.	Which of the following has the highest bond order? (A) N2 (B) O2 (C) He2 (D) H2	Answer: (A)
14.	Which of the following gives an aldehyde on dry distillation? (A) Calcium acetate + calcium benzoate (B) Calcium formate + calcium acetate (C) Calcium benzoate (D) Calcium acetate	Answer: (B)
15.	Which of the following does not give benzoic acid on hydrolysis? (A) phenyl cyanide (B) benzoyl chloride (C) benzyl chloride (D) methyl benzoate	Answer: (C)