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Understanding ChemistryUnderstanding Chemistry

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What is Chemistry?What is Chemistry?

Chemistry is the study of thecomposition, structure, properties and

interactions of matter.

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Chemistry Related CareersChemistry Related Careers

Aquaculturist

Bacteriologist

Biochemist

Chemical engineer

Cosmetic scientist Doctor

Environmental scientist

Food technologist

Forensic scientist

Geologist

Laboratory technician Nutritionist

Pathologist

Pharmacist

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In chemistry, all matter is considered as

chemical. Thus, chemicals are not only

found in laboratories, but also in commonsubstances such as air, water, soil and

metals.

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Scientific InvestigationScientific Investigation

Scientific Method

The scientific method or scientific process is

fundamental to scientific investigation and to the

acquisition of new knowledge based on physicalevidence by the scientists.

Scientists use observations and reasoning to propose

tentative explanations for natural phenomena, termed

hypotheses. The scientific method is a systematic approach to

research. It consists of the following steps:

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1. Making observation

An investigation usually begins with an observation

on a phenomenon.

Observation is to observe and gather theinformation about the phenomenon.

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2. Making Inference

After gathering sufficient information, we make an

inference, or early conclusion, based on what has

been observed. The inference may or may not be trueand need to be proven true or false with further

investigation.

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3. Identifying problem

Asking question based on the inference madeto identify the problem related to the

observation.

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4. Making a hypothesis

A hypothesis is a proposed explanation for a

phenomenon.

Normally, it is a general statement about the

relationship between the manipulated

variable and a responding variable in order

to explain the question ask.

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5. Identifying variables

A variable is a factor that affects other factors in anexperiment.

In a scientific investigation, we need to identify allrelated variables.

There are three types of variable, namely

Manipulated variable the factor that ispurposely changed in an experiment

Responding variable the factor that changeswith the manipulated variable

Fixed variables the factors that are keptconstant throughout an experiment. This is to

ensure that other factors do not affect the resultsof the experiment.

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6. Controlling variables

Deciding how to repeat the experiment several

times by using different values of the manipulated

variable. This step is to test the consistency in the

experiment and also to relate the manipulated

variable to the responding variable.

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7. Designing the experiment

Deciding how to carry out the experiment, including

determine the material, apparatus, experiment sets

out and the procedure to take. Always keep in mind that the main purpose of the

experiment is to o test the hypothesis.

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8. Carrying Out the Experiment

- After the planning of the experiment is done,

you will need to carry out the experiment

according to the procedure.

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9. Collecting data

Make observations in the experiment by watching

and measuring.

Measure the quantities accurately using suitablemeasuring instruments and units.

All data are collected and recorded in a proposed

table.

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10. Analysing and interpreting data

After collecting the data, you will need to analyse

the results of the experiment.

Data analysis is the step to studies information bybreaking it down into smaller parts.

The results can be presented in various forms, such

as a table, graph or chart.

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11. Making a conclusion

Draw conclusions based on the observations and

results.

State whether the hypothesis is true or false.

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12. Writing the report

A report is written after an experiment is performed.

The format of the report is arranged based on the

scientific investigation method which is performed

systematically; starting from the problems identified

to the last stage.

State any precautions taken to overcome problems

in the experiment.

A simple diagram of the experiment set-up would

sometime be useful.