5. Primary succession occurs when pioneer species move into an area that has no plants. Which organisms are common pioneer species?
A Conifer trees and tall grasses with roots that loosen the soil
B. O Mosses and lichens that can grow on rocky surfaces
c. Grasses and weeds that arrive as seeds carried by the wind and then germinate in rich soil
D. O Vines and shrubs that help prevent the erosion of shallow soil
No

C

Explanation:

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.