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/ Everyone who ate oysters got sick.
/ Bacteria in the oysters may have caused the illness.
/ Symptoms include nausea and dizziness
/ The cooks felt really bad about it.
/ People got sick whether the oysters were raw or cooked.
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A hypothesis is an assumption or tentative explanation. The other statements are observations.
2. Which of the following statements is a law?
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/ Higher altitude means lower boiling points for water, all other things held equal.
/ An egg cooked for 27 minutes in Baltimore was badly overcooked.
/ An egg cooks in 17 minutes at sea level.
/ An egg takes less time to cook in Baltimore than in Denver.
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A law is a general description of a pattern or a relationship, the rest are observations
3. The statement, "Osmium has a density of 22.59 g/mL, which makes it the densest element known" is an example of:
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/ a theory / / a hypothesis
/ an experimental observation / / a law
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The statement isn't a law because it is specific; laws are generalized descriptions of patterns or relationships. The statement isn't a hypothesis because it isn't tentative. It isn't a theory because it doesn't explain any observations.
4. A natural law is
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/ a description of a pattern or relationship in experimental data
/ an explanation that has been proved
/ a tentative explanation for a natural phenomenon
/ obeyed under any circumstances.
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See below for further clarification of law
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ADDED BACKGROUND:
A hypothesis is a provisional or working explanation, assumed true only to guide experimentation or for the sake of argument. A theory is a well established explanation
A law is just a description of a pattern in the data. A theory is an explanation for the pattern. The law shows what happens, without explanation. A theory explains how it happens, often by using using an analogy or metaphor. So whether a hypothesis that becomes well established becomes a law or a theory depends on whether it tells you what happens, or it tells you how something happens.
A law (natural law) is a description of the data; it is not necessarily fact. If new data comes to light that violates the law, it must be amended or discarded. Because laws usually are based on a vast body of data, gathered over a long period of time and reviewed by many investigators, it's very rare for a law to be discarded. Apparent 'violations' of natural laws are easy to contrive if you ignore the restrictions on the data that the law is based on. When experimental fact is in conflict with a law, the law must be either corrected or discarded. This is a rare occurrence, because laws must summarize a large body of experimental data before they're elevated to law status. But it does happen.
The Scientific MethoD
- a systematic procedure for solving problems and exploring natural phenomena
- Observations (data)
- are the foundation of the scientific method
- data can be qualitative or quantitative.
- data is most useful when collected under controlled conditions
- Natural laws
- compactly summarize patterns in a large amount of data
- often apply only under special conditions
- are descriptions of nature, not facts or explanations
- Hypotheses
- tentative explanations designed to guide experimentation
- a useful hypothesis must be testable
- must be rejected or corrected when they conflict with experiment
- Theories
- a well-tested explanation for experimental data based on a set of hypotheses.
- must be discarded or refined when they can't explain new experimental results
- scientific theories have three aspects: philosophical, mathematical, and empirical.
- Understand all three, or risk misusing the theory!
- a Good theory...
- explains currently available data
- is as simple as possible (but no simpler!)
- accurately predicts results of future experiments
- suggests new lines of work and new ways to think
- clearly shows underlying connections