A thousand ways to pass basic chemistry examination

1.Each 325mg tablet of aspirin consists of 195.0mg carbon, 14.6mg hydrogen and 115.4mg oxygen. Determine its empirical formula (C=12, H=1, O=16).
  • A. C₈H₉O₄
  • B. C₉H₈O₄
  • C. C₆H₈O₄
  • D. C₉H₄O₈
2.Identify the number of reacting units in the reaction. Cr₂O₇²⁻ + 6H -----> 2Cr³⁺ + 7H₂O
  • A. 4
  • B. 8
  • C. 6
  • D. 2
3.Zinc oxide is a
  • A. basic oxide
  • B. acidic oxide
  • C. amphoteric oxide
  • D. neutral oxide
4.The periodic classification of elements is an arrangement of the elements in order of their
  • A. atomic weights
  • B. isotopic weights
  • C. molecular weights
  • D. atomic numbers
5.A small quantity of solid ammonium chloride (NH₄Cl) was heated gently in a test tube, the solid gradually disappears to produce two gases. Later, a white cloudy deposit was observed on the cooler part of the test tube. The ammonium chloride is said to have undergone
  • A. Distillation
  • B. sublimation
  • C. precipitation
  • D. evaporation
6.A volume of 42.5ml 0.125M KOH is needed to neutralize completely 37.2ml of H₃PO₄ solution. Find the molar concentration of H₃PO₄.
  • A. 0.480M
  • B. 0.068M
  • C. 0.048M
  • D. 0.084M.
7.The number of dissolved particles in solution does not depend on one of the following
  • A. Strong electrolyte
  • B. weak electrolyte
  • C. non-electrolyte
  • D. oxidation number.
8.An element X forms the following compounds with chlorine XCl₄, XCl₃, XCl₂. This illustrates the
  • A. Law of multiple proportion
  • B. Law of chemical proportions
  • C. Law of simple proportions
  • D. Law of conservation of mass
9.When air which contains the gases oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases left are;
  • A. Nitrogen and carbondioxide
  • B. The rare gases
  • C. Nitrogen and oxygen
  • D. Nitrogen and the rare gases
10.When large hydrocarbon molecules are heated at high temperature in the presence of a catalyst to give smaller molecules, the process is known as
  • A. Disintegration
  • B. polymerization
  • C. cracking
  • D. degradation
11.When each of the nitrates of potassium, magnesium and iron is heated,
  • A. All the nitrates dissolve to their oxides
  • B. the nitrate of magnesium gives the nitrite and oxygen
  • C. the nitrates of magnesium and iron give the oxides
  • D. the nitrate of iron gives the nitrite and oxygen
12.A sample of hard water contains some calcium sulphate and calcium hydrogen carbonate. The total hardness may therefore be removed by
  • A. Boiling the water
  • B. Adding excess calcium hydroxide
  • C. Adding a calculated amount of calcium hydroxide
  • D. adding magnesium hydroxide
13.What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?
  • A. steam distillation
  • B. destructive distillation
  • C. liquefication
  • D. hydrolysis
14.Detergents have the general formula ___
  • A. R(CH₂)ₙOH
  • B. RSO₃⁻Na⁺
  • C. RCO₂⁻Na+
  • D. RCO₂H
15.The formula of the compound formed in a reaction between a trivalent metal M and a tetravalent nonmetal X is ___.
  • A. MX
  • B. M₃X₄
  • C. M₄X₃
  • D. M₃X₂.
16.2.25g of a sample of an oxide of copper on reduction gave 2.0g of copper. 2.50g of another oxide of copper on reduction also gave 2.0g of copper. These results are in accordance with the law of __
  • A. constant proportion
  • B. definite proportion
  • C. multiple proportions
  • D. conservation of matter
17.One mole of propane is mixed with five moles of oxygen. The mixture is ignited and the propane burns completely. What is the volume of the product at s.t.p?
  • A. 112.0dm³
  • B. 67.2dm³
  • C. 56.0dm³
  • D. 44.8dm³.
18.The rate of a reaction is proportional to the number of effective collisions occurring per seconds within the reactants. This statement is associated with the
  • A. Kinetic theory
  • B. rate law
  • C. gas law
  • D. collision law
19.A zero order reaction is one
  • A. In which the reaction rate does not depend on the concentration of the reactants
  • B. In which the reaction rate depends on the concentration of the reactants.
  • C. In which the rate depends on the temperature of the reaction mixture
  • D. All of the above
20.Which of the following physical properties decreases across the periodic table?
  • A. ionization potential
  • B. electron affinity
  • C. electronegativity
  • D. atomic radius