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Science Experiments
Experiments often conducted by students to test different scientific theories and hypotheses
11,111 Questions
What is the control and the variable in a science fair project?
Controls are used to show that the test, equipment, procedure...are working properly. One would expect negative controls to give negative results and positive controls to give positive results. Controls used would depend on the experiment.
Can a hypothesis be disproved by a single experiment.?
Yes. A hypothesis describes what we expect to happen in an experiment. If we do the experiment and something different happens, then our hypothesis is "falsified", or demonstrated to be false.
In that case, we'll need to reconsider our hypothesis to determine how it was wrong. We can revise our hypothesis and then conduct a different experiment to test it.
It's easy to demonstrate that a hypothesis is incorrect, but it is impossible to prove that it is true.
Can you explain the difference between physical changes and chemical changes?
Physical changes is change in property. Ex) change from solid to liquid....ice to water. Chemical change changes to different substances. Ex) rotting of fruit.
What do we have to write for Analysis for an experiment?
You have to discuss and analyse your results, identify any trends, relationships and patterns in your data, also you have to find explanations for your results and support with scientific judgements, reasoning and arguments.
You also could use books or do some research at this point to explain your findings.
What are the five properties of air?
air takes up space
AIR HAS pressure
air has no odor(usually)
air has mass
air has no colour (usually)
What is the purpose of a control group conducting a research study?
So you can see if the thing your testing really had an effect. For instance, if you just took ten mice and gave them ecstasy, yes, they might do soe,thing interesting, kr they might not, but whatever happens, you have no way of knowing if that is different from a normal mouses behavior. You need a group that is under conditons that are as close as possible to the treatment group(s), except for the variable you are tesing, so the. You know any difference between the groups is a result of the variable. Of course, to be sure you should use statistical analysis to see if the differences are statistically significant. For instance, if you were testing types of ferilizer, and half of the plants in your test group rew a foot tall, while the rest grew around six incues, even if all the plants in the control group grew shorter than all the plants in your treatment group(s), you couldnt comclude that fertilizer had an effect on plant height, since there was such a discrepancy between the olants in your comtrol group. What it come down to is this: you want the differences between groups to be greater than the differences between samples with in your groups.
Can bubbles be made with water?
Bubbles cannot just be made with plain water; you need to add soap or something else like that. Shampoo, bubble bath, soap etc...
What happens when you put a 9 volt batery on your tongue?
It delivers a very mild electric shock. Just a tiny little zap. Try it, it's fun, and it tastes reall funny. Just be sure to use only a little 9 volt like you put in a walkman or radio.
What is a catchy title for an experiment about candles?
In order to discover whether white and colored candles burn at different rates, you would need the following:
- Several sets of candles of identical size, shape, and manufacturer (more likely to have similar chemical composition), but of varying colors
- An accurate timing device
- A yardstick or ruler for measuring length
- A chart or document to record initial lengths, measured lengths, and time of burning for each separate candle (or set of identical ones)
Procedure :
- Candles are set up in a safe, fire-proof, ventilated area away from any combustible materials. When handling heated candles, insulated kitchen gloves should be worn.
- Candles are separated into groups by size, the only obvious difference being their color. Multiple colors are used. By size, these could include common birthday candles, religious or votive candles, cooking candles, and emergency lighting candles.
- A common point of measurement is established, as opposed to waiting for the candles to fully expend. For example, this could be half of the original length. Candles may be marked to make this easier to observe.
- Each set is measured and burned separately (except for very long-burning candles), and the times noted for each. Ideally, you should use more than one of each type to avoid possible manufacturing defects that could skew the data.
The data is recorded and arranged in a table, possibly with visual charts showing the candles and the times. (Vertical bar charts, which resemble the candles, are effective illustrations.)
A summary of the data : which burned slower or faster in each group, whether this was consistent in all types of candles, and conclusions that might be drawn. Other data such as the percentage difference in burning rate, and how that varied by size, could also be included.
What are some good science fair projects for 9th graders?
There are many simple science experiments that could be conducted for a 9th grade class. Magnetic field experiments, soil erosion prevention, heat loss prevention, and determining the Vitamin C level in certain foods and beverages are all examples.
Is it OK to heat a flammable liquid such as ethanol using water bath over a Bunsen flame?
No, it is not safe to heat a flammable liquid such as ethanol over a Bunsen flame as it can lead to a fire or explosion. It is best to use a heating mantle or hot plate to safely heat flammable liquids. Heating it indirectly with a water bath is also a safer option.
In an experiment what is a variable?
it is anything you can experiment on in you project
The variable in the experiment allow you to test alternate possible situations and solutions to confirm the validity if the experiment or to disprove it.
Does pepper affect the boiling point of water?
Pepper has the least effect on the temperature or reaction to boiling water ,As well pepper does not dissolve in boiling water like other grains.
Any Research science fair project on static electricity?
Well, you can try this experiment- it is 'What happens when static electricity is discharged?' It's in the category of Physics-Electricity. Hope this helps!
What are manipulated variable and responding variable?
the manipulated variable is the part of the experiment that is changed. the dependent variable is the part of the experiment that does not get changed(stays the same throughout the experiment), and the scientist use it to record the data.
What is a repeatable procedure?
An experiment which can be repeated and will yield the same results. Ex. If x+y=z in the experiement if you try the experiment again you should get the same result "z".
What liquid is advisable to use as liquid inside the thermometer mercury or alcohol?
Rather ironically, it depends on the temperatures involved. Most thermometers use mercury. Partly, this is because the silver colour of the mercury make it easy to read, but mainly because they work over a useful range of temperatures for everyday use.
However, one problem with mercury is that its melting point is -38oC; so below that temperature the thermometer would freeze - this makes it unsuitable for use in very cold environments.
Alchohol thermometers (usually ethanol is used) work from around -115oC, so they are used in low temperature environments - the disadvantage with alcohol is that it vaporises at 78oC so it isn't useful in very hot environments.
What are the three types of models used in science?
The answer is Physical, Computer, and Idea. These are the types of models. These models can be used in everyday life.
What are the different ways of communicating scientific information?
there are many different ways which communicate scientific information the scientific information doesn't come straight away from scientists all the time.
scientific informatin come from posters, presentation, newspapers, or the tv and radios. some times it also came from speaking to friends and family
i hope that helps
