Chemistry Worksheet

(Part A) Writing Questions

1. What happens to the rate of reaction when magnesium ribbon is added to dilute sulfuric acid?

The rate of reaction increases quickly at first because magnesium reacts with sulfuric acid to
produce hydrogen gas.

2. How can you measure the rate of reaction in the magnesium ribbon experiment?

Measure the volume of hydrogen gas produced over time using a gas syringe or an inverted
measuring cylinder.

3. Why does the rate of reaction between magnesium and sulfuric acid slow down over time?

Because the concentration of sulfuric acid and magnesium decreases, resulting in fewer
collisions between particles.

4. What does the steepness of the slope on a graph of reaction rate indicate?

A steeper slope means a faster reaction rate.

5. Explain how temperature affects the rate of reaction and why?

Higher temperature increases the rate because particles move faster and collide more often
with enough energy to react.

6. How does surface area affect the rate of reaction? Explain with an example of magnesium
reacting with oxygen.

More surface area means more particles are exposed to react. For example, magnesium
powder reacts faster with oxygen than a magnesium strip because it has a larger surface area.

7. What is an anomalous result, and how can you identify it on a graph?

An anomalous result is one that doesn't fit the pattern of the other data points. It appears as a
point far from the trend line on a graph.

8. According to particle theory, why does the rate of reaction change over time in the
magnesium ribbon experiment?

As the reaction goes on, acid particles are used up, so there are fewer successful collisions,
slowing down the reaction.
9. What equipment would you need to measure the rate of reaction between calcium carbonate
and hydrochloric acid?

Conical flask

Gas syringe or measuring cylinder

Stopwatch

Balance

Measuring cylinder

10. How can you ensure the reliability of your results when measuring the rate of reaction?

Repeat the experiment to get reliable results.

11. When magnesium ribbon is added to dilute sulfuric acid, what gas is produced?

Bubbles of hydrogen.

12. What is meant by the rate of reaction?

How quickly or slowly a reaction happens.

13. Explain one way by which we can collect the hydrogen gas produced?

One way to collect hydrogen gas is by attaching a syringe to the top of a flask so that no
hydrogen gas can escape.

14. Write the word and symbol equations for the reaction of magnesium with sulfuric acid?

Word equation: Magnesium + Sulfuric acid → Magnesium sulfate + Hydrogen

Symbol equation: Mg + H₂SO₄ → MgSO₄ + H₂

15. Write the word and symbol equations for the reaction of copper carbonate with hydrochloric
acid?

Word equation: Copper carbonate + Hydrochloric acid → Copper chloride + Carbon dioxide +
Water

Symbol equation: CuCO₃ + 2HCl → CuCl₂ + CO₂ + H₂O

16. What is the collision theory and how is it related to the rate of reaction?

Collision theory says particles must collide with enough energy for a reaction. More collisions
mean a faster reaction, helped by heat, concentration, or surface area.

17. When you put magnesium ribbon near a Bunsen burner, will the reaction be fast, slow, or no
reaction?

When magnesium ribbon is heated near a Bunsen burner, it reacts quickly with oxygen in the air
to make magnesium oxide. The heat gives it energy to react faster.

18. How does the surface area affect the rate of reaction?

A larger surface area speeds up the reaction because more particles are exposed and can
collide with others more often.

19. Which of the results is anomalous. Explain how you have identified the anomalous result,
and say what you would expect the result to be?

The anomalous result is 26 cm³ at 90 seconds because it doesn't follow the increasing trend of
the other volume.

20. What is the difference in reaction between magnesium cube, ribbon, and powder and why?

Magnesium Cube: The reaction is slow because the cube has a smaller surface area exposed
to the reactants.
Magnesium Ribbon: The reaction is faster than the cube because the ribbon has a larger
surface area, allowing more collisions between magnesium and other particles.

Magnesium Powder: The reaction is the fastest because the powder has the largest surface
area, allowing for the most frequent and effective collisions.

21. Write the word and symbol equations for the reaction of copper carbonate with hydrochloric
acid?

Word Equation: Copper carbonate + Hydrochloric acid → Copper chloride + Water + Carbon
dioxide

Symbol Equation: CuCO₃ + 2HCl → CuCl₂ + H₂O + CO₂

22. Write the word and symbol equations for the reaction of magnesium with sulfuric acid?

Word Equation: Magnesium + Sulfuric acid → Magnesium sulfate + Hydrogen

Symbol Equation: Mg + H₂SO₄ → MgSO₄ + H₂

23. Write the word and symbol equations for the reaction of magnesium with oxygen?

Word Equation: Magnesium + Oxygen → Magnesium oxide

Symbol Equation: 2Mg + O₂ → 2MgO

24. As the reaction came to an end, fewer bubbles were produced, why?

It's because as the reaction progressed, the reactants were used up, slowing the reaction rate.
This led to fewer bubbles being produced.

(Part B) Fill in the blanks

1. When magnesium ribbon reacts with dilute sulfuric acid, bubbles of hydrogen gas are given
off.

2. The rate of reaction can be measured by timing how much of one of the reactants has been
used up.

3. In the magnesium ribbon experiment, the reaction started faster, but slowed down over time.
4. The steepest part of the graph shows the period when the reaction is fastest.

5. To measure the rate of reaction, you can attach a Syringe to the top of a flask.

6. The total volume of hydrogen gas produced can be read from the markings of the syringe.

7. An anomalous result does not fit the pattern shown in the table or graph.

8. At the start of a reaction, there are a lot of collisions between particles.

9. In a block of magnesium, most of the atoms are inside the block. In magnesium ribbon, most
of the atoms are on the surface to react. Magnesium ribbon has a larger surface area than a
magnesium block. An equivalent mass of magnesium powder has an even larger surface area

10. To measure the rate of reaction between calcium carbonate and hydrochloric acid, you can
collect the hydrogen gas over water.

(Part C) Circle the correct answer

1. What gas is produced when magnesium ribbon reacts with dilute sulfuric acid?

a) Oxygen

b) Carbon dioxide

c) Hydrogen

d) Nitrogen

2. How can you measure the rate of reaction between magnesium and sulfuric acid?

a) By measuring the temperature change

b) By timing how much magnesium is left

c) By measuring the volume of hydrogen gas produced

d) By counting the bubbles of sulfuric acid

3. Why does the rate of reaction slow down over time?

a) The magnesium ribbon increases in mass

b) There are fewer collisions between particles

c) The sulfuric acid becomes more concentrated

d) The hydrogen gas escapes too quickly

4. What does a steeper slope on a reaction rate graph indicate?

a) The reaction is slowing down

b) The reaction is becoming constant

c) The reaction is faster

d) The reaction has finished

5. What equipment is used to measure the volume of gas produced in the magnesium ribbon
experiment?

a) A thermometer

b) A gas syringe

c) A balance

d) A stopwatch

6. What happens if hydrogen gas escapes during the experiment?

a) The reaction speeds up

b) The volume of gas measured will be inaccurate

c) The magnesium ribbon dissolves faster

d) The sulfuric acid becomes more dilute

7. What is an anomalous result?

a) A result that fits the pattern perfectly

b) A result that matches the expected outcome

c) A result that does not fit the pattern

d) A result that occurs at the start of the reaction

8. According to particle theory, what happens at the start of a reaction?

a) There are fewer collisions

b) There are a lot of collisions

c) The particles stop moving

d) The particles form a gas

9. What gas is produced when calcium carbonate reacts with hydrochloric acid?

a) Hydrogen

b) Oxygen

c) Carbon dioxide

d) Nitrogen

10. How can you improve the reliability of your results in a reaction rate experiment?

a) Use a different acid each time

b) Take measurements only once

c) Repeat the experiment and take consistent readings

d) Use less reactant each time