Civil Engineering - Waste Water Engineering - Discussion

When the quantity of acids in the rain water is more than the average, then such rain is called 'Acid rain'.

We are aware that normally rainwater has a pH of 5.6. When the pH of the rainwater drops below 5.6, it is called acid rain.

Acid rain refers to how acid from the atmosphere is deposited on the earth’s surface.

Oxides of nitrogen and sulphur which are acidic can be blown by the wind along with solid particles in the atmosphere and finally settle down either on the ground as dry deposition or in water, fog and snow as wet deposition.

The average pH value of the acid rain is 4 to 5.

Normal, clean rain has a pH value of between 5.0 and 5.5, which is slightly acidic.
However, when rain combines with sulfur dioxide or nitrogen oxides "produced from power plants and automobiles" the rain becomes much more acidic.
Typical acid rain has a pH value of 4.0.

The normal rainfall ph is 5.6 which is also known as unpolluted air.

Anything lower than 5.6, which is 5 or lower, as stated in the choices, is considered to be acidic for rain.

The rainfall is acidic when it's below 7.
Not 7.
7 is neutral.

Then answer is below 7,
It could be 6, 5, 6.5.

But according to Indian Standard. If pH is less than 5 then only it could be considered as acid rain.

According to IS (Indian standard), 5.0 is the standard value. So, option C.5 is the correct answer.

Lower the ph value higher the acidity.

So, among these 5 is the lowest.

pH=7 will be neutral.

Answer for acidic rain can be 5, 6, even 6.5.

I think less than 7 is called acidic. Answer should be B.

Actually, the standard value of pH for acid rain is 5.6.