soalan latihan - rate of reaction
TRANSCRIPT
SOALAN 1
A magnesium ribbon of 5 cm in length is added into four acid solutions. In which of the following acid solutions will the magnesium ribbon dissolve in the shortest time?
A- 100 cm3 of 2.0 mol dm-3 hydrochloric acid B-200 cm3 of 2.0 mol dm-3 nitric acid C- 100 cm3 of 1.5 mol dm-3 sulphuric acid D- 100 cm3 of 2.0 mol dm-3 ethanoic acid
SOALAN 2
Manganese(IV) oxide increases the rate of decomposition of hydrogen peroxide by
A- increasing the activation energy of the reaction. B - increasing the kinetic energies of the hydrogen
peroxide molecules. C- increasing the number of effective collisions
between the hydrogen peroxide molecules. D- increasing the rate of collisions between the
hydrogen molecules.
SOALAN 3
Which of the following mixtures has the highest initial rate of reaction?
A - 5 g zinc powder and hydrochloric acid of
concentration 0.2 mol dm-3. B- 10 g zinc powder and hydrochloric acid of
concentration 0.1 mol dm-3. C- 5 g solid zinc metal foil and hydrochloric acid of
concentration 0.2 mol dm-3. D-10 g zinc metal foil and hydrochloric acid of
concentration 0.2 mol dm-3.
SOALAN 4
2MnO42- (ak) + 5C2O42- + 16H+
10CO2 + 2Mn2+ + 8H2O The equation above represents the
reaction between permanganate(VII) ions with oxalate ions (C2O ). If excess potassium permanganate is used, the rate of the above reaction can be determined by measuring
A -time taken for the Mn2+ ions to form. B-time taken for the concentration of oxalate
ions to drop to zero. C -time taken for the purple colour of the
permanganate(VII) ions to decolourise. D-time taken to collect the carbon dioxide gas
at every minute interval.
SOALAN 5
Experiment Reactants Average rate of reaction
I 10 g of small marble chips with 50 cm3 of 1.0 mol dm-3 hydrochloric acid.
x
II 10 g of small marble chips with 50 cm3 of 2.0 mol dm-3 hydrochloric acid.
y
III 10 g of large marble chips with 100 cm3 of 1.0 mol dm-3 hydrochloric acid.
z
The table above shows the average rate of
reaction between marble and hydrochloric acid solutions. Arrange the average rate of reaction of the three experiments in increasing order.
A- y, x, z B -x, y, z C-z, y, x D-z, x, y
SOALAN 6
8.
Experiment Volume of hydrochloric
acid /cm3
Concentration of
hydrochloric acid/mol dm-3
III
50100
1.00.5
Two experiments are carried out to study the rate of evolution of carbon dioxide gas by adding 10g (excess) of marble chips into hydrochloric acid solutions as shown in the table above.
Which of the following graphs of volume of carbon dioxide against time correctly represents the results of the two experiments?
A
B
C
D
SOALAN 7
The curve P is obtained from the catalytic decomposition of 20 cm3 of 0.5 mol dm-3 of hydrogen peroxide at 30oC. What changes to the hydrogen peroxide solution will produce a curve represented by Q?
Volume of
hydrogen peroxide/
cm3
Concentration of hydrogen
peroxide/ mol dm-3
Temperature/oC
A 20 0.5 30B 10 0.5 40C 20 0.5 40D 10 1.0 30
SOALAN STRUKTUR
Experiment I and experiment II have done to investigate the effect of total surface area on the rate of reaction.
Experiment I : 50 cm3 of 0.1 mol dm-3
hydrochloric acid is added to 6.0 g of big crushed marble chips. Experiment II : 50 cm3 of 0.1 mol dm-
3 hydrochloric acid is added to 6.0 g of powder marble chips.
The total volume of gas that is released for the both experiments are recorded for every 30 seconds. The results obtained from the both experiments as in Table 5 below.Time/s
Masa /s0 30 60 90 120 150 180 210 240 270 300
Volume of gas /cm3
Isipadu gas / cm3
Experiment IEksperimen I
0 12 23 32 40 48 56 61 68 74 78
Experiment IIEksperimen II
0 22 40 56 68 77 84 89 93 95 98
Write the chemical equation for the reaction in the both experiments.
[ 2 marks] By using the same axes, draw a graph of
volume of gas against time for experiment I and experiment II in graph sheet.
[ 3 marks]
By referring to the graph, calculate the rate of reaction for experiment I and experiment II at 120 seconds.
[ 2 marks]
Based on the calculations in (c), state the relationship between total surface area of marble with the rate of reaction.
……………………………………………………………………………………………........[ 1 mark]
If the both experiments is carried out until no more gas is released, is there any differences of total volume of gas released at the end of these experiments.
…………………………………………………………………………[ 1
mark]
Give a reason for your answer.
…………………………………………………………………………[ 1 mark]