What Is a Real Hypothesis?
A hypothesis is a tentative statement that proposes a possible explanation to some phenomenon or event. A useful hypothesis is a testable 
statement which may include a prediction.
When Are Hypotheses Used?
The key word is testable. That is, you will perform a test of how two variables might be related. This is when you are doing a real experiment. You are testing variables. Usually, a hypothesis is based on some previous observation such as noticing that in November many trees undergo colour changes in their leaves and the average daily temperatures are dropping. Are these two events connected? How?
Any laboratory procedure you follow without a hypothesis is really not an experiment. It is just an exercise or demonstration of what is already known.
How Are Hypotheses Written?
- Chocolate may cause pimples.
- Salt in soil may affect plant growth.
- Plant growth may be affected by the color of the light.
- Bacterial growth may be affected by temperature.
- Ultra violet light may cause skin cancer.
- Temperature may cause leaves to change color.
All of these are examples of hypotheses because they use the tentative word “may.”. However, their form is not particularly useful. Using the word may does not suggest how you would go about proving it. If these statements had not been written carefully, they may not have even been hypotheses at all. For example, if we say “Trees will change color when it gets cold.” we are making a prediction. Or if we write, “Ultraviolet light causes skin cancer.” could be a conclusion. One way to prevent making such easy mistakes is to formalize the form of the hypothesis.
Formalized Hypotheses example: If skin cancer is related to ultraviolet light , then people with a high exposure to uv light will have a higher frequency of skin cancer.
If leaf color change is related to temperature , then exposing plants to low temperatures will result in changes in leaf color.
Notice that these statements contain the words , if and then. They are necessary in a formalized hypothesis. But not all if-then statements are hypotheses. For example, “If I play the lottery, then I will get rich.” This is a simple prediction. In a formalized hypothesis, a tentative relationship is stated. For example, if the frequency of winning is related to frequency of buying lottery tickets. “Then” is followed by a prediction of what will happen if you increase or decrease the frequency of buying lottery tickets. If you always ask yourself that if one thing is related to another, then you should be able to test it.
Formalized hypotheses contain two variables. One is “independent” and the other is “dependent.” The independent variable is the one you, the “scientist” control and the dependent variable is the one that you observe and/or measure the results. In the statements above the dependent variable is underlined and the independent variable is underlined and italicized.
The ultimate value of a formalized hypothesis is it forces us to think about what results we should look for in an experiment.
Thanks for this, it proved to be helpful.
However, I do have a few questions. Obviously different teachers or instructors have their own requirements for their classes.
How would you write an appropriate Question to follow each purpose in your lab report?
For example: If the purpose was, “To obtain dissecting skills in an observational lab,” what question could you formulate with the purpose? (which is answered in the hypothesis)
And if a teacher requires the hypothesis to be in the format “If, Then, Because” how should this be written? I can actively complete the if and then, but I’m unsure how to incorporate the “because’ statement. For example, “If pigs and humans share the same nutritional behaviors, then their internal organs should function comparably and look relatively the same.” (how do i incorporate because?)
If the purpose of your lab is “To obtain dissecting skills in an observational lab,” you can’t really formulate a testable hypothesis for that. I’ll assume you are doing some kind of pig or frog dissection. Often teachers give general outlines of skills that students are meant to ascertain from an experiment which aren’t necessarily what the actual experiment is directly testing. Obviously to do the dissection lab you need to obtain dissection skills but testing that would be rather subjective unless the teacher provided you with standards or operationally defined “dissecting skills”. If I were you, I would obviously mention it in the introduction of your lab but I am not sure if your teacher wants you to actually format it as a hypothesis; you can ask your teacher for clarification. If making a hypothesis from each purpose was some arbitrary exercise assigned to you then, it could look like this:
“If a student has successful acquired dissection skills, then they will be able to complete this observational lab with satisfactory competence because they utilized these newly acquired skills.”
For the “If, Then, Because” hypothesis…you pretty much have it. You would modify what you posted: “IF pigs and humans share the same nutritional behaviors, THEN their internal organs should look relatively the same BECAUSE of similar function and composure.” That is an example. For the “If, Then, Because” you should follow this guideline:
IF X and Y both do or share this, THEN this should be found/confirmed, BECAUSE of this fact or logical assumption.
Would have been better if more examples were given
Is there such thing as a if/and statement? I am in 8th grade science an I need to know for my lab report due tomorrow.HELP!!!!
@Lauren
An if/and statement is not usually apart of the convention. What exactly do you need help with?
I really need help for onion skin lab hypothesis for class