Practical Work: Rate of Reaction
Investigating how the rate of reaction is affected by the concentration of liquid reactants.
Background information:
The rate of reaction for a reactant or product in a particular reaction is defined as how fast or slow the reaction takes place. This experiment uses the chemical reaction of zinc and hydrochloric acid to observe how the concentration of acid effects the rate of reaction.
Hydrochloric acid + zinc = zinc chloride + hydrogen
Zn + 2 HCl --> ZnCl2 + H2
In this experiment the chemical reaction is measured by the amount of bubbles produced.
Research Question:
How is the rate of reaction affected by the concentration of liquid reactants?
Hypothesis:
The rate of reaction will increase as the concentration of acid increases.
Variables:
Independent:
- concentration of hydrochloric acid
Dependent:
- the amount of bubbles produced
Controlled:
- same amount of zinc
- scale
- testtubes
- amount of acid
- measuring cylinder
Materials:
- 4 pieces of 10g zinc
- 4 different high solutions of hydrochloric acid (0.1m, 1m, 2m, 3m)
- 4 testtubes
- scale
- measuring cylinder
- testtube holder
Risk Assessment:
Wear goggles at all times to protect your eyes. Wear a lab coat to protect your clothes. Handle the acid with care and follow the
directions of your teacher.
Procedure:
1. 10ml 0.1 were measured and poured into a test-tube.
2. Then a piece of 10g zinc was weighed and added to the solution in the test-tube.
3. After that the amount of bubbles produced was observed and noted.
4. Steps 1-3 were repeated with hydrochloric solutions of 1m, 2m and 3m.
Results:
Amount of Bubbles produced in each test:
|0.1m hydrochloric acid|1m hydrochloric acid|2m hydrochloric acid|3m hydrochloric acid|
Amount of
bubbles produced|no bubbles / no reaction|small amount of tiny bubbles produced|more and bigger bubbles produced|most amount of bubbles...