SCIENTIFIC METHOD
Science is a system of organized knowledge.
It trends to be
• objective,
the scientific method attempts to minimize the influence of the scientist's bias on the
outcome of an experiment & conclusions that follow.
• testable,
The scientific method is based upon evidence, not on belief. A scientist remains
skeptical of anything but good evidence.
• explanatory,
provides cause- to-effect relation, reduces the observed phenomena to
something we already know & understand
• predictive,
permits to foresee the outcome of certain experiments, or
sequences of observed events
• tentative
Scientific statements are rarely final, any time they may
need adjustment, when new facts are discovered
The scientific method is the process by which scientists construct an accurate (that is,
reliable, consistent & non-arbitrary) representation of the world.
Science operates through:
• Observations, which may be qualitative(color, smell) or quantitative (amount of
product in a chemical reaction, duration of a reaction).
Caution is necessary since things are not necessarily what they seem to be.
(it seems that the right line is longer than the left one, but in fact they are equal)
• Experiment: observation under controlled conditions.
Scientists use an experiment to search for cause & effect relationships in nature.
One variable is introduced in each experiment.
• Hypotheses: a tentative explanation to be verified & modified by further
experiments
- an educated guess
- a statement that relies on a few observations
- an idea based on observations without,& before experimental proof
A successful hypothesis develops into a theory
• Theory is a unifying principle that explains a broad class of facts & observations. &
Theories & Models: explain & predict a broad range of phenomena
- use many observations and has loads of experimental proof
- can be applied to facts that seemed unrelated before
- flexible enough to be modified if new data/proof introduced
• Laws of Nature:
highest level, most general, universal statements, usually in a mathematical form, to which no
exceptions are known.
In science, we first formulate the problem (question)
Then collect information (our own observations, or literature, or both)
Then suggest an explanation, a tentative cause & effect relationship (hypothesis)
Then set experiment with results that can be tentatively predicted from the hypothesis
If the outcome agrees with our prediction – more experiments must be set, varying conditions,
until either no exceptions could be found (then a general theory is formulated), or limits are
determined where that theory is applicable.
The basic knowledge & concept behind all & every explanations in chemistry is that of
atomic structure of matter.
Atomic structure is a matter of fact.
We are able to visualize separate atoms (as Si atoms in silica lattice).
Chemists play with atomic models to obtain new combinations of atoms, first, as models, then
by real chemical reactions.
Molecular models: as simple as that
of water, H2O
or benzene, C6H6
or as complex as a protein, with thousands of atoms, as this myoglobin