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Identify and discuss the differences between the terms ‘theories,’ ‘laws,’ and ‘hypotheses.’ Describe ‘controlled conditions.’

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Hypotheses are guesses, statements made on limited evidence which can be used as a foundation for further investigation.  The word actually comes from the Greek meaning "under placement." Well-tested hypotheses can become theories, or a system of arguments that can explain a given phenomena.  Theories can lead the way to the discovery of facts, from which Laws of cause and effect can derive.

Theories and hypotheses are neither Laws nor facts. Hypotheses guess why something happens; theories explain why something happens, and Laws dictate what will happen.

Controlled Conditions are conditions set as a standard for comparison to verify the results of an experiment.

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LawsThe term "Law" in science is a debatable one. A good scientist would say that the term "Law" and its implications are inherently unscientific and do not belong in a scientific dialogue. This is because a scientist should always be open to the possibility of error or contradiction; calling something a Law, in the sense that it is a rule that is never broken, is an inherently unscientific premise. Even if we are 99.9% certain that something will be a certain way, good science does not make the leap of presumption to 100%.

However, there are less volatile definitions of the term Law. Most of the time, we use the term more loosely, to suggest something which has been repeatedly observed and confirmed through those observations, and which we assume to be true under future conditions. Observations which describe a "what", and not a ""how" or "why" are also called Laws, because they do not involve a hypothesis.

HypothesesSometimes hypotheses are called "educated guesses". A good hypothesis is a proposal or prediction that can be tested, measured, repeated by others, and independently confirmed. A complete hypothesis might say "X is hypothesized to be red; this will be tested by placing the object in a spectrometer and analyzing its light spectrum, and comparing that spectrum to the red range of light wavelengths."

TheoryA theory is a hypothesis that has been repeatedly tested and shown to be consistent. The hypothesis does not necessarily have to be retained in an unaltered form; in fact many hypotheses undergo revision on their way to being considered a theory. There is no definite line between what is considered a theory and a hypothesis; a hypothesis can be tested 5 or 500 times and not necessarily be a theory. Status as a theory is largely a result of the agreement of the relevant academic community.

Controlled ConditionsThe only thing that all "controlled conditions" have in common is that they are designed by humans toward a specific intention. The world and its interactions are complex; by limiting those interactions by controlling them artificially, we can get a better idea of which things affect each other and which do not. Controlled conditions often seek to reduce or eliminate variety so that only the things that remain are available to influence one another.

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A theory is an idea that a scientist has that has.  There is evidence that goes against it, but there may be other ways to explain the reason for the phenomenon. For example, the big bang theory.

A law is a rule that has never been disproven.  It has strong support and is followed every time.  Think of the law of gravity, or Newton's laws.

A hypothesis is an educated guess or prediction to the outcome of an experiment or event.  When you perform an experiment, your teacher will probably ask you to make a hypothesis to what the results of your experiment will be.  A hypothesis generally has not yet been tested, and will be supported or unsupported based on the results of experimentation.

If a hypothesis is repeatedly tested, it has the possibility to become a theory, or a law.  It must also be accepted by the scientific community to be considered such.

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Identify and discuss the differences between the terms ‘theories,’ ‘laws,’ and ‘hypotheses.’ Describe ‘controlled conditions.’  ****the question is based on chemistry - organic, biological, and general****

Laws are things which are known to be true in all cases.  For example, the law of gravity tells us that if we are on Earth and jump off a chair, we will fall to the ground.  This is indisputable and will always be a fact.

A theory is an explanation of experimental information which has a significant amount of evidence to support it.  To achieve the status of "theory", there must be multiple experiments or extensive data to support the statement of the theory.  For example, atomic theory proposes information about the structure of an atom.  However, at this point in time, we cannot physically look inside an atom and determine the location of electrons in the atom but we have significant evidence that supports the theory of how they are distributed in orbitals.

A hypothesis is a proposed explanation of a phenomenon that has either a theoretical background to support it or some preliminary experimental results which suggest that the hypothesis is reasonable but not enough evidence is available that we can call it a theory or a law.

Controlled conditions means to control as many variables as you can when doing an experiment so as you change one variable, you can monitor the effects on the results.  By changing only one variable at a time, we can use that information to have a better understanding of the reaction or chemical phenomenon.

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Identify and discuss the differences between the terms"‘theories",  "laws", and "hypotheses".   Describe "controlled conditions".

The difference between a theory and a law is that the law has been proven true so many times it is generally held to be one universal truth.  The law of universal gravitation, commonly known as the law of gravity, works every time, with objects accelerating towards the Earth, with little difference in the outcome.  Theories, on the other hand, are explanations of questions scientists have, but have not undergone the rigorous, extensive proving methodology laws have been subjected to.  The theory of general relativity, published and put forth by Albert Einstein in the early 20th century, still is being tested and reviewed today.  A hypothesis is, at best, an educated guess as to the outcome of a scientific experiment.  Hypotheses do not always have to be correct;  many important scientific discoveries have been made at the expense of a hypotheses being wrong.

Controlled conditions in a scientific experiment are the factors we don't think makes the difference in the outcome of the experiment.  Therefore, we want to make sure those factors are the same in each experimental trial, to control them, so no one may say we changed them and that was what produced the results of our experiment.

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