Adama Science and Technology University
Division of Freshman Program (Pre-Engg)
Quiz-1- General Chemistry
Course Code: Chem1101
Max. Marks- 10 Max Time- 30 Mins.
Q1. J.J. Thomson proved that cathode rays were beams of _____.
(A) alpha particles
(B) atoms
(C) electrons
(D) oil droplets
Q2. What experiment provided evidence for Thomson's atomic model?
(A) The gold foil experiment
(B) The cathode ray tube experiment
(C) The nuclear magnetic resonance experiment
(D) The electron diffraction experiment
Q3. In Rutherford’s gold foil experiment, some of the alpha particles passed straight through
the gold foil, completely undeflected. What could Rutherford conclude from this
observation?
(A) Alpha particles have a positive charge.
(B) Electrons have a positive charge.
(C) The atom is made up of mostly empty space.
(D) There must be a small, positively charged dense area within the atom.
Q4. Which of the following has a positive charge?
(A) proton
(B) neutron
(C) anion
(D) electron
(E) atom
Q5. A sample of a hydrocarbon was combusted producing 1.054 g of CO2 and 0.2168 g of
H2O. What is the empirical formula for the hydrocarbon?
(A) C1H1
(B) C1H2
(C) C2H2
(D) C2H1
Q6. Which of the following is NOT an empirical formula?
(A) C6H14O
(B) C6Na2O6
(C) C14H8O5
(D) C4H8N3
Q7. What is the empirical formula for a compound that contains 37.69% Na and 62.31 %
Fluorine?
(A) NaF3
(B) Na2F
(C) NaF
(D) NaF2
Q8. If the reaction of 125 grams of C6H6O3 reacts in excess of oxygen (O2) and produces 51
grams of H2O, what is the percent yield?
(A) 80%
(B) 85%
(C) 101%
(D) 95%
Q9. An oxide of lead contains 90.65% Pb, by weight. The empirical formula is:
(A) Pb
(B) PbO
(C) Pb3O4
(D) Pb2O3
(E) PbO2
Q10. Silicon nitride (Si3N4) is made by combining Si and nitrogen gas (N2) at a high
temperature. How much (in g) Si is needed to react with an excess of nitrogen gas to prepare
125 g of silicon nitride if the percent yield of the reaction is 95.0%?
(A) 89 g
(B) 79.1
(C) 75 g
(D) 90.8 g
Q11. In the following reaction-
O3 + NO → O2 +NO2
200 g of O3 is treated with 400 g of NO. Calculate-
(a) Which of the two reactants is the limiting reagent?
(b) Calculate the mass of NO2 formed.
(c) How much excess reagent (in gram) is left at the end of the reaction?