Ascientist conducted an experiment to test the hypothesis that maple seeds exposed to acid
rain will take longer to germinate than seeds exposed to normal rain, which has a ph of 5.6. the
scientist set up four groups, each containing 200 maple seeds. the water used for each group had
a different ph value: 5.6.4.0.3.0. and 2.0. all other conditions were kept the same. after ten
days, the number of seeds that had germinated in each group was counted.
identify the control group in this experiment?

 the control group was grown at a pH of 2

Explanation:

Seeds comprise a radicle, which descends and becomes the root system; the endosperm, containing stored food; an epicotyl, which develops into the stem and the seed coat that protects the seed. which are small food storage organs and plant embryos encased in a seed coat. These embryos require specific conditions in order to break their dormancy; seed dormancy is a temporary state in which plant development and growth are halted, until specific conditions required for germination to occur. Conditions required for seed germination:

During the germination process, plants emerge from the seed and start growing. However, the delicate tissue structures can be damaged by low pH; this can occur due to acid rain, where the pH of the rainwater is lowered by the presence of pollutants.

Due to the presence of atmospheric carbon dioxide, normal rain’s pH is typically around 5.6, and in heavily polluted areas with other gases as pollutants, acid rain’s pH can range from 3-4. A highly acidic pH of 2 can denature enzymes required for germination and seed growth; apart from causing damage to the entire seed, there’s no expected growth at this pH range making it a suitable control.

Experimental controls give valuable information about the experiment’s conditions and validity; they are usually carried out in the same conditions as the other experiments, but the independent variable (pH) is usually changed.

the correct answer: the index of refraction of the second medium is lower i tried this persons answer and it was wrong this person is lying

well first you need the sample of the temperature and gas level. i couldnt write a hypothesis unless i had some data. i think temperature changes will effect volumes of gas because gas changed into a solid or liquid at specific temperatures.