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09/08/2019

chemistry essays, please help?

QUESTION
chemistry essays, please help?
i need a bit of information on these three topics so i anyone has anything and can tell me there sources that would be great.
Acid rain is a major environmental problem facing our society. In an organized presentation discuss: (a) the sources of acid rain; (b) the chemistry of rain including equations for important reactions; (c) an explanation of pH and the use of pH measurements to determine acidity; (d) the effects of acid rain on the environment; and (e) some ideas on solutions to this worldwide problem.

Choose any two topics. Each concerns a laboratory task. In a well-constructed paragraph, explain in detail how you would perform each task. Specify all necessary equipment, amounts of materials needed, and procedures used with necessary calculations. You may number the steps rather than answer this in a paragraph form.

List four factors and explain how they affect the rate of solution of a solid in a liquid.

ANSWER
For the first topic:
Acid rain is produced when certain greenhouse gases dissolve in water to produce a weak acid that can cause damage to buildings, soil and crops etc. For example, if CO2 dissolves in water:
CO2 + H2O –> H2CO3 (carbonic acid)
or for NO2: NO2 + H2O –> H2NO3 (nitric acid)

pH is a measure of the acidity of a substance. pH = -log[H+] where [H+] is the concentration of H+ (i.e. the concentration of acid) in the solution. A higher [H+] results in lower pH, indicating higher acidity

Acid rain is a major problem for the environment as it can absorb into the soil, increasing soil pH and making it difficult for crops to grow. It can also leak into underground water supplies and erode natural limestone supplies (limestone is mostly Ca(OH)2, which reacts with the acid: Ca(OH)2 + 2H+ –> Ca2+ + 2H2O)

So far the main suggested solution is to reduce the level of greenhouse gas emissions. You can probably look up more on Google

The second topic I can’t really help with unless the actual topics are given. These kind of things are usually based on labs you’ve already done though, so I would go through any notes if you have them

The third topic – grinding the solid into powder will increase the rate of dissolution as there is more surface area available to interact with the water molecules. Increasing the temperature also tends to increase dissolution rate as the molecules in the solid are given more energy allowing them to break out of their bonds to the other solid molecules and form bonds with oxygen instead. Not sure about another two factors but you can probably Google it