A thousand ways to pass basic chemistry examination

121.Given the reaction at equilibrium: N₂(g) + O₂(g) ↔ 2NO(g) as the concentration of N2(g) increases, the concentration of O₂(g) will
  • A. decrease
  • B. increase
  • C. remains the same
  • D. vanishes
122.If a reaction is exothermic and there is a great disorder, it means that
  • A. The reaction is in a state of equilibrium
  • B. There will be a large increase in free energy
  • C. There will be a large decrease in free energy
  • D. The reaction is static.
123.In the chemical reaction of A + B = C +D, more of D is formed
  • A. if the concentration of A is reduced
  • B. if the concentration of B is reduced
  • C. if the concentration of C is reduced
  • D. if it is continuously removed from the reaction mixture
124.In what way is equilibrium constant for the forward reaction related to that of the reverse reaction?
  • A. The addition of the two is expected to be one.
  • B. The product of two is expected to be one.
  • C. The two equilibrium constants are identical
  • D. The product of the two is always greater than one
125.In which reaction will the point of equilibrium shift to the left when the pressure on the system is increased?
  • A. C(s) + O₂(g) ↔ CO₂(g)
  • B. CaCO₃(s) ↔ CaO(s) + CO₂(g)
  • C. 2Mg(s) + O₂(g) ↔ 2MgO(s)
  • D. 2H₂(g) + O₂(g) ↔2H₂O(g)
126.The furring of kettles is caused by the presence in water of __
  • A. calcium trioxocarbonate (IV)
  • B. calcium tetraoxosulphate
  • C. calcium hydroxide
  • D. calcium hydrogentrioxocarbonate (IV)
127.Which is a property of a reaction that has reached equilibrium?
  • A. The amount of products is greater than the amount of reactants.
  • B. The amount of products is equal to the amount of reactants.
  • C. The rate of the forward reaction is greater than the rate of the reverse reaction
  • D. The rate of the forward reaction is equal to the rate of the reverse reaction
128.Which of the following combination of conditions may increase the rate of a chemical reaction.
  • A. Decrease in temperature, increase in concentration of the reactant
  • B. Increase in temperature, addition of a catalyst, decrease in the surface area of the reactant
  • C. Increase in temperature, increase in concentration, addition of a catalyst and increase in the surface area of the reactant
  • D. Decrease in temperature, concentration and surface area of the reactants
129.“Quicklime” has the formula __
  • A. Ca(OH)₂
  • B. CaO
  • C. CaCO₃
  • D. CaSO₄.2H₂O
130.A Transition metal is different from a non-transition metal because
  • A. it has an octet configuration
  • B. it is very stable
  • C. it is coloured
  • D. it has incomplete outer shell d-electrons
131.Chlorine is produced commercially by
  • A. electrolysis of dilute HCl
  • B. electrolysis of brine
  • C. neutralization of HCl
  • D. heating potassium trioxochlorate (V)
132.Chlorine, bromine and iodine resemble one another since they __
  • A. dissolve in alkalis
  • B. react violently with H2 without heating
  • C. displace each other from solutions of their salts
  • D. are gases
133.Liquid oxygen may be produced by condensation of air using this coolant
  • A. liquid
  • B. liquid gas
  • C. liquid paraffin
  • D. liquid nitrogen
134.One of these is another form of oxygen
  • A. hydroxide
  • B. ozone
  • C. peroxide
  • D. sulphoxide
135.One of these metals is not an alkali metal
  • A. K
  • B. Cs
  • C. Sr
  • D. Rb
136.One of these reactions represents the laboratory preparation of hydrogen.
  • A. C(s) + H₂O(l)→ CO(g) + H₂(g)
  • B. 2 Na(s) + 2H₂0(1) → 2 NaOH(aq) + H₂(g)
  • C. Cu(s) + H₂O(l) → CuO(s) + H₂(g)
  • D. Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g)
137.The formation of ozone by reaction of O₂ with atomic oxygen in UV light occurs in
  • A. upper atmosphere.
  • B. inner atmosphere.
  • C. stratosphere
  • D. hemisphere
138.The halogen which is chiefly produced commercially from sea water is ___
  • A. Fluorine
  • B. chlorine
  • C. Bromine
  • D. iodine
139.The most stable allotropic form of sulphur at normal conditions is ___
  • A. monoclinic sulphur
  • B. rhombic sulphur
  • C. amorphous sulphur
  • D. plastic sulphur
140.The products obtained when the following chemical reaction is completed and balanced are…HNO3 + Ca(OH)2 → ______
  • A. CaNO₃ + H₂O
  • B. Ca(NO₃)₂ + 2 H₂O
  • C. CaO + 2 NO₂ + 3H₂O
  • D. Ca + 2 NO₃ + 2 H₂O