Chemistry B Final Exam

Design a controlled experiment using scientific method

What is the project?

Part of a chemistry class is being able to design and carry out a controlled experiment. We have spent the year learning scientific method, a way scientists can communicate and collaborate their findings in a similar uniform format. We have also learned lab safety procedures and techniques to be successful in the laboratory.

Your challenge is to create a controlled experiment that follows the scientific method to test a hypothesis. You must have independent and dependent variables, constants, and a control group in order for it to be a valid controlled experiment.

You have free range over which type of experiment you create, as long as we can get the materials for class next week. Your experiment must not be dangerous to those who preform it, and it must also be able to be conducted during the allowed amount of exam time.

Your experiment should also include at least 3 things that would need to be calculated in the data analysis section of the lab write-up.

Step 1:

research different types of experiments or chemical reactions that can be safely preformed

here are some helpful sources:

you will need to come up with at least a couple of different reactions you could do, just in case they will not be good to create a lab based off of.

you may use flinn scientific or other science supply companies as resources

other good chemical reactions often come from household chemical reactions

you can also take a cool chemical reaction that you have seen and create a lab out of it where you are creating a controlled experiment

keep these things in mind:

-it must be a controlled experiment, where you have a control group and an experiment group and you are only changing 1 variable.
-it must be preformed within the allowed exam time

-it must be safe for all members preforming it

-it must be calculating something in the end (at least 3 calculations)

- you may choose moles, stoichiometry, gas laws, or a calculation you can teach yourself such as calculating H+ from pH or thermochemistry or kinetics

- 2 of your calculations can be graphs that you will have to analyze but at least one has to be a math calculation problem

Step 2:

Each member of your team must Fill out a lab write up with the following information

a) Get together with your lab team and create a question or problem you want to answer.

this will be the basis for the lab and will help you create your hypothesis.

b) run through your procedure and materials making sure each step would be clear and precise

(pretend like you would have a freshman run your experiment, make sure they know every single thing they are supposed to do, and how to do it)

c) make sure all variables and constants are listed so that the experimenter knows what they are looking for and keeping constant.

Independent- I change (what are you changing between your 3 trials)

Dependent- What are you measuring/figuring out in your lab

Control group - usually your first trial, the one you compare the others to, or the one that you designed the experiment around

3 Constants- things that stay the same for your experiment to work

d) create your hypothesis based on which you think will do better or worse, and what you are testing

(remember your hypothesis should be a TESTABLE IF/THEN statement) if the hypothesis is not what you want someone to test and be able to support/not support then it is not a good hypothesis

Remember this will be worth 40 points of your grade, based on the rubric

Step 3

On exam day your group will carry out your experiment. and another group will observe and use the 40 point rubric to grade your lab.

You will carry out the lab writing down observations and data

and then you will run the calculations

and complete the lab write up

safety and carrying out the lab is worth 10 points

calculations and data analysis are worth 30 points

and your conclusion and new questions are worth the other 20