PRACTICE QUESTIONS 001

practice paper 001
CHM 101 CHEMISTRY Time: 20 mins
1) which of the following is not one of the properties of alpha particles? (a) they have high velocities (b) they are deflected to the negative poles of electro static fields (c) they have a high penetrating power (d) they can ionize gases readily.
2)A process in which heavy nuclei split into smaller ones is known as (a) nuclear fusion (b) nuclear fission (c) atomic radiation (d) chemo nuclear splitting.
3) The most common oxidation state exhibited by an atom with electronic configuration 1S² 2S² 2P⁴ would be (a) -1 (b) -2 (c) -3 (4) 5
4) At what temperature is the entropy of all systems zero (a) 0°C (b) 20°C (c) 20K (d) 0K
5) which of the following would favour spontaneity of chemical reactions (a) + ∆H (b) - ∆H (c) + ∆S (d) - ∆S
6) For a thermodynamic reaction at chemical equilibrium, the value of Gibb's free energy is (a) negative (b) positive (c) undefined (d) zero
7)which of the following DOES NOT play an important role in determining spontaneity of chemical reactions (a) entropy (b) mass (c) enthalpy (d) fee energy
8) The oxidation number of Mn in K2MnO4 is NOT (a) +2 (b) a and c (c) +7 (d) +6
9) For an endothermic reaction (a) ∆H > 0 (b) ∆H < 0 (c) ∆G = 0 (d) ∆S > 1
10) For the reaction N2(g) + O2(g) <=> 2NO(g) ∆H = +2 Kj/mol The equilibrium will shift to the right if (a) temperature is increased (b) Some nitrogen is removed (c) some nitrogen monoxide is added (d) pressure is lowered
11) The oxidation number of Mg in MgO is (a) -3 (b) +3 (c) +2 (d) -1
12) Calculate the volume of CO2 produced during the combustion of 2.32g of glucose. [GMV at stp = 22.4 dm³. C=12 H=1 0=16] (a) 0.67dm³ (b) 0.77dm³ (c) 0.29dm³ (d) 1.73dm³
13)The short notation of the element with atomic number 20 is (a) [Ar]1S¹ (b) [Ar]1S² (c) [Ar]3S² (d) [Ar]4S²
14) calculate the [H+] ions in coca cola if it's PH is 2.50 (a) 3.2×10^-2 (b) 7.11×10 ^ -5 (c) 3.2×10^-3 (d) 9.9×10^1
15) If the concentration of hydrogen ions in a solution is 3.8×10^-6M, calculate the PH (a) 5.41 (b) 6.03 (c) 4.89 (d) 7.00
16) a solution has a PH of 10.40. What is its [OH-]? (a) 1.0×10^-7 (b) 2.52×10^-4(c) 2.52×10^4 (d)1.0×10^7
17) calculate the number of molecules in 2g of water [N = 6.02×10^23] (a) 6.69×10^22 (b) 6.69×10^-22 (c) 3.01×10^22 (d) 3.01×10^-22
18) The following affect rate of one way chemical reactions except (a) temperature (b) pressure (c) concentration of reactants (d) concentration of products
19) 22.4ml of NaOH is needed to titrate 25ml of HCl. Calculate the molar concentration of the acid, if 0.5M of base is used. (a) 0.0277M (b) 0.0227M (c) 0.0488M (d) 0.0448M
20) The oxidation number of Cr in K2Cr2O7 is (a) +2 (b) +5 (c) +6 (d) +7 Note: Stick to the time duration to help yourself. click here for solutions