Question

A student decides to set up an experiment to see if detergent affects the growth of seeds. he sets up 10 seed pots. 5 of the seed pots will receive a small amount of detergent in the soil and will be placed in the sun. the other 5 seed pots will not receive detergent and will be placed in the shade. all 10 seed pots will receive the same amount of water, the same number of seeds, and the same type of seeds. he grows the seeds for two months and charts the growth every 2 days. what is wrong with his experiment?

Answer 1

By placing the pots with detergent in the sun and the pots without detergent in the shade, the student is not comparing the effects that detergent has in the growing rate of the seeds under the same conditions; besides, he does not have a control group. Therefore, he will not be able to determine if the growing rate of the plants were affected by the detergent, the lack of sunlight, or a combination of both factors.