Chemical kinematics, equilibrium and energetics questions | form three Chemistry

In the graph below, curve 1 was obtained from the decomposition of 100 cm³ of 1.0M hydrogen peroxide solution catalysed by manganese (IV) oxide, .

Which alteration/change to the original experimental conditions would produce curve 2?
A Lowering the temperature
B Using less manganese IV oxide
C Increasing the temperature
D Adding some 0.1 M
E Using a different catalyst.

Answer / Solution

UNSOLVED

Two experiments were carried out using the same mass of magnesium ribbon and the same volume of acids of the same concentration. The acids were 1M hydrochloric acid and 1M ethanoic acid. The results were as shown in the following figure:

(a) If the experiments were conducted within the same time, is there a difference in volumes of hydrogen gas collected at the same room temperature and pressure? Give reasons for your answer.
(b) When same mass, volume and concentration of powdered magnesium and ethanoic acid are allowed to react, new graph is formed. Giving reason (s), suggest the position of that graph whether will be above, between or below graphs A and B.

Answer / Solution

UNSOLVED

A student attempted to prepare hydrogen gas by reacting zinc metal with dilute sulphuric acid. In this experiment zinc metal granules of about 0.5 cm diameter and 0.20 moles of acid were used. The rate of formation of hydrogen gas was found to be slow.
(a) Explain three ways in which the rate of formation of hydrogen gas could be increased.
(b) If the student wanted 36 cm 3 of hydrogen gas at s.t.p, what amount of the acid would be required.

Answer / Solution

UNSOLVED

State and describe the type of reaction in the following chemical equations:

Answer / Solution

UNSOLVED

In the following equilibrium equation, the forward reaction is exothermic. Which change would increase the production of sulphur trioxide at equilibrium?

1. Increasing temperature.
2. Decreasing temperature.
3. Decreasing sulphur trioxide concentration
4. Decreasing pressure
5. Adding a catalyst.

Answer / Solution

UNSOLVED