Q.1
To slow down a chemical reaction you will do one of the following:
  • Place the reactants in hot water
  • Place the products in ice bath
  • Place the reactants in an ice bath
  • Keep stirring the reactants with a stirring rod
Q.2
The following equation shows the reaction between calcium carbonate, CaCO3 and hydrochloric acid, HCl:CaCO3(aq) + 2HCl(aq) → CaCl2(aq) + CO2 (g)­­ + H2O(l)Which of the following is the suitable method to measure the rate of reaction?
  • Change in the temperature of the solution with time
  • Change in the volume of carbon dioxide gas with time
  • Change in the mass of water with time
  • Change in the concentration of hydrochloric acid with time
Q.3
More collisions correspond to a:
  • Faster reaction rate
  • Slower reaction rate
  • Constant reaction rate
  • None of the above
Q.4
Hydrochloric acid can react with sodium thiosulfate solution to form a sulfur precipitate. The equation is:Na2S2O3(aq) + 2HCl(aq) → 2S(s) + SO2(g) + 2NaCl(aq) + H2O(l)In a second experiment, an extralmL of water is added to the hydrochloric acid. As a result of this change, the
  • rate of evolution of the sulfur dioxide decreases
  • precipitate will form more quickly
  • more fruitful collision will occur
  • reaction will not be affected because water is not a reactant
Q.5
Why does breaking up a solid reactant increase the rate of reaction?
  • it creates more solid
  • it creates more energy
  • it increases the total surface area
  • it increases the concentration
Q.6
Increasing pressure causes the reacting particles
  • to bond together
  • to repel from each other
  • gain more kinetic energy
  • to move closer together
Q.7
Catalyst helps to
  • increase the amount of product obtained
  • to lower the activation energy
  • provide an alternative reaction route
  • decrease the frequency of collision
Q.8
Which manufacturing of the following is not a characteristic of catalyst?
  • A catalyst is specific in its reaction.
  • A catalyst influences the quantity of product of a reaction.
  • The chemical property of a catalyst remains unchanged at the end of the reaction.
  • Only a little amount of a catalyst is needed to influence the rate of reaction.
Q.9
Magnesium reacts with acid to produce hydrogen gas, H2.Which solution would give the highest initial rate of reaction?
  • 100 cm3 of 1.0 mol dm-3 of nitric acid, HNO3
  • 100 cm3 of 1.0 mol dm-3 of hydrochloric acid, HCl
  • 100 cm3 of 1.0 mol dm-3 of sulphuric acid, H2SO4
  • 100 cm3 of 1.0 mol dm-3 of ethanoic acid, CH3COOH
Q.10
Which of the following reactions occurs at the highest rate?
  • Photosynthesis
  • Rusting of iron
  • Combustion of hydrogen in oxygen
  • Combustion of magnesium in oxygen
Q.11
The following equation represents the reaction between calcium carbonate, CaCO3 and hydrochloric acid, HCl.CaCO3 + 2HCl --> CaCl2 + CO2 + H2OWhich changes can be used to determine the rate of reaction?I : mass of calcium carbonate per unit timeII : Volume of carbon dioxide released per unit timeIII : Colour of solution per unit timeIV : Mass of precipitate produced per unit time
  • I and II
  • I and III
  • II and IV
  • III and IV
Q.12
The reaction between zinc, Zn and hydrochloric acid, HCl is represented by the following equation.Zn + 2HCl --> ZnCl2 + Hstudent wants to determine the rate of reaction in a school laboratory. Which of the following methods is the most suitable?
  • Determine the change in temperature of the solution with time
  • Determine the change in the concentration of zinc chloride with time
  • Determine the volume of hydrogen gas given off with time
  • Determine the change in the concentration of hydrochloric acid with time
Q.13
In which of the chemical reactions can the rate be determined by measuring the change in the gas volume?
  • Acidified potassium manganate (VII) solution with iron (II) sulphate solution
  • Sodium hydroxide solution with dilute hydrochloric acid
  • Silver nitrate solution with sodium chloride solution
  • Calcium carbonate with dilute hydrochloric acid
Q.14
The rate of reaction for the decomposition of hydrogen peroxide decreases with time because
  • product of reaction decreases
  • temperature of hydrogen peroxide decreases
  • volume of hydrogen peroxide decreases
  • concentration of hydrogen peroxide decreases
Q.15
Which reactions has the highest rate of reaction?
  • Rusting of water pipe
  • Photosynthesis in green plant
  • Burning of a small piece of charcoal in the air
  • Formation of stalactites and stalagmites
Q.16
Which of the following has the lowest rate of reaction?
  • Combustion of ethanol
  • Fermentation of glucose
  • Oxidation of magnesium
  • Precipitation of silver chloride
Q.17
Which unit is correct for the rate of reaction?
  • g mol-1
  • g min-1
  • mol dm-3
  • kJ mol-1
Q.18
Smaller particle size allows for a _________ surface area to be exposed for the reaction.
  • larger
  • smaller
  • rectangular
  • spherical
Q.19
Increasing the ____ causes the particles (atomsor molecules) of the reactants to move more quickly so thatthey collide with each other more frequently and with moreenergy.
  • Catalyst
  • Surface Area
  • Temperature
  • Concentration
Q.20
Pick the TWO (options that will INCREASE the rate of a reaction.
  • Adding Heat
  • Adding Catalyst
  • Removing Catalyst
  • Both A & B
0 h : 0 m : 1 s