Home CHEMISTRY TOPIC 4: SCIENTIFIC PROCEDURES | CHEMISTRY FORM 1

TOPIC 4: SCIENTIFIC PROCEDURES | CHEMISTRY FORM 1

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TOPIC 4: SCIENTIFIC PROCEDURES | CHEMISTRY FORM 1

Significance of scientific procedure

The Concept of Scientific Procedure

Explain the concept of scientific procedure

The scientific method (procedure) is a process that scientists use to ask questions and conduct investigations to find answers to these problems.

It is a logical approach to problem solving by observing and collecting data, formulating hypotheses, testing hypotheses, and formulating theories that are supported by data. The scientific method provides a standardized way for scientists to conduct their work. However, many scientists work according to other methods as well.

The Importance of the Scientific Procedure
Explain the importance of the scientific procedure Includes
  1. The scientific procedure makes a researcher or an experimenter more
    systematic and organized when investigating or solving a problem.
  2. It gives a means by which one can get a solution to several questions
    about natural phenomena, e.g. why does water expand when it freezes?
  3. It may lead to discoveries and innovations.
  4. Provides background knowledge upon which future references may be made.
  5. It makes our sense organs more effective in exploring our natural world. That is, we become more sensitive to environmental changes.
  6. It makes us use the available resources more sustainably in solving everyday problems.
  7. Assists us in predicting the future outcome based on the present condition.
  8. Assists us in testing the validity or the possibility of an event, phenomenon or problem.
The
scientific procedure is used in many areas and in different fields of
study. It is especially applied by scientists and researchers to find
solutions to various scientific problems. Below are some of the areas
where the scientific procedure is applied:
  1. In scientific research:
    Researchers normally apply the scientific method when conducting
    researches on diverse scientific problems or phenomena. A researchable
    problem whose solution is sought for without following the correct
    sequence of the steps of the scientific method is not likely to get
    resolved.
  2. In a field study: A field study (or
    field work) is often conducted to find answers to problems or test
    hypotheses. It involves doing some practical work that applies the
    scientific methods.
  3. When conducting experiments:
    An experiment is a methodical procedure carried out with the goal of
    verifying, falsifying, or establishing the accuracy of a hypothesis.
    Experiments vary greatly in their goals and scale, but always rely on
    repeatable procedure and logical analysis of the results.
  4. In project work:
    A project is a planned piece of work that involves careful study of a
    subject or problem over a period of time, so as to find information on
    the subject or problem.
The Scientific Procedure to Carry Out Investigations in Chemistry
Use the Scientific procedure to carry out investigations in chemistry
In
this chapter, we have used two major examples to explain the concept of
experimental procedure in detail. These are the rate of evaporation of
water and exposure of anhydrous copper (II) sulphate powder to open air.
For easy understanding and quick reference by students, the two
examples are summarized below. Note that the test for the anhydrous
copper (II) sulphate powder was not explained in full. However, the
summary can give you a good picture on how to go about experimenting it.
A. The rate of evaporation of water
Steps
  1. Problem/question: Does surface area affect the rate of evaporation of water?
  2. Hypothesis: Evaporation of water increases with increases in surface area
  3. Experimentation:
    A basin and a bucket are filled with 10 litres of water each. They are
    left exposed to open air, under similar conditions for a period of 3
    days.
  4. Observation and data collection: After 3 days, the remaining water in containers was measured carefully. The results were recorded in a table.
  5. Data analysis and interpretation:
    It was found that 3 litres of water had evaporated from the basin and
    1.5 litres from the bucket. From this data, it was discovered that much
    water (3 litres) had evaporated from a container with large surface area
    (basin) as compared to only 1.5 litres of water that had evaporated
    from a container with a small surface area (bucket).
  6. Conclusion:
    Since a large amount of water evaporated from the basin as compared to
    that from the bucket, it is correct to conclude that surface area
    affects the rate of evaporation of water and that the larger the surface
    area the higher is the evaporation. Therefore, the hypothesis is proved
    to be true.
B. Exposure of anhydrous copper (II) sulphate powder to open air
Steps
  1. Problem/question: Why does anhydrous copper (II) sulphate powder change into hydrated blue crystals when exposed to open air?
  2. Hypothesis:
    When exposed to open air, the anhydrous copper (II) sulphate powder
    absorbs water vapour from the air and this water vapour turns it to blue
    crystals.
  3. Experimentation: The anhydrous sulphate is
    exposed to open air to absorb sufficient water vapour. Then the hydrated
    sulphate is heated to drive out all the liquid in it.
  4. Observation and data collection:
    The sample of hydrated blue crystals loses the liquid in it and turns
    to its original white powder. The vapour given off is carefully
    collected, cooled down to liquid, and then put in a beaker or test tube.
  5. Data analysis and interpretation:
    The collected liquid is subjected to various water tests to justify
    whether it is water or just the other liquid substance. The liquid is
    identified as water.
  6. Conclusion: The anhydrous copper
    (II) sulphate was exposed to air only. We also know that air contains
    water vapour. Because of this reason, it is correct to conclude that the
    water came from the water vapour contained in air. The water turned the
    white powder to blue crystals. Therefore, our hypothesis is true.
Activity 1
Aim: To find out if chalk dissolves in water
Materials:
Beakers, tap water, pieces of chalk, mortar and pestle, sieve,
crucible, stirring rod, source of heat, tripod stand, match box and
sticks, tongs.
Procedure:
Note: Before you start, formulate a hypothesis for the experiment.
  1. Take four pieces of blackboard chalk and break them into halves.
  2. Put the broken pieces of chalk in a mortar and pestle.
  3. Use the pestle to grind the chalk into a fine powder. To obtain the finest powder, sieve the resulting powder with a sieve.
  4. Put the sieved chalk dust in a beaker.
  5. Add water to the chalk dust in a beaker until it is half-full.
  6. Stir the mixture vigorously for about 15 minutes.
  7. Let the mixture settle overnight. Observe whether any dissolution has occurred.
Questions for discussion
  1. What hypothesis did you formulate?
  2. Could you see any particles of chalk after stirring?
  3. Could you still see any particles after settling?
  4. Is your hypothesis false or true?
  5. Draw a conclusion based on your findings.

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