In chemistry what is a variable and a control?

Say you are doing an experiment to see if sugar effects how a child behaves. You have two children (or groups of children).





Control - The control group would be the children who receive no sugar in their diet.





Variable - The variable in the experiment would be the children you feed candy or sugar to.In chemistry what is a variable and a control?
In any scientific experiment, a variable is something that changes. You should only have one or two variables. Variables are what is different in an experiment: for instance, if you have an experiment with several plants in varying amounts of sunlight, and you are trying to find out how that affects plant growth, you should keep everything else the same: species of plant, amount of water a plant gets, food, etc. These CONTROLled factors are the controls of an experiment.In chemistry what is a variable and a control?
Control = reference subject.





Variable = reference subject + experimentation





Quick example...





I'm doing an experiment to see what effect 3 different methods of burning oak wood has on the wood (silly, I know, but it's just an example). My control would be an unburned piece of oak wood. My variables would then be three other pieces of oak wood that I burn with three different methods of burning.





This doesn't just apply to chemistry, by the way. Controls and variables are used through pretty much all sciences.





Hope that helps.
A variable is something you change (vary) to see how the results differ with each experiment.


A control is something that remains the same in each experiment.