<em /><em>The single factor that is changed in an experiment is the <u>Independence variable.</u></em>
Answer:
oxygen and carbon dioxide
A. Soil erosion
the watering of the plants and the sowing and reaping of the crops would lead to erosion
Answer:
YELLOW
Explanation:
Phenol red is a biological indicator used to monitor changes in pH. The phenol red indicator changes color ranging from yellow to pink with respect to changes in pH. In an acidic pH i.e. <7, the phenol red changes to a YELLOW color while in an alkaline pH i.e. >7, the phenol red changes to a PINK pH.
The presence of carbon dioxide (CO2) increases the hydrogen ion concentration (H+) of a solution (lowering its pH or making it acidic).
Therefore, in a reaction where CO2 is created as a product, it means the CO2 content of that solution increases. Hence, the phenol red solution will be shifting towards the YELLOW color in response to a decreasee in pH (acidic).
