Horrendous air pollution in India

India is once again heading into the worst time of year for air pollution, a season where the country’s notoriously poor quality becomes even more toxic. The main cause of deteriorating quality of air is- petrol and diesel-based vehicle exhaust fumes, coal and petroleum power plants, exhaust from industrial plants and factories and other human activities. Burning of fossil fuels releases carbon dioxide, methane, nitrogen and particulates into the atmosphere. A whopping nine in 10 people on Earth breathe highly polluted air, and more than 80 percent of urban dwellers have to endure outdoor pollution that exceeds health standards, according to the WHO’s World Global Ambient Air Quality Database. Cities like Kanpur, Faridabad, Delhi, Varanasi and Patna are polluted badly by vehicles and have large number of coal and petroleum-based industries.

Drawing on measurements and calculations as of 2016 from air monitoring stations in 4,300 cities, the WHO reported in March that India’s cities suffer the most.

Cities with the highest small particulate measurements in the world

Country	City	PM2.5 (µg/m³)
IndiaIndia	KanpurKanpur	173173
IndiaIndia	FaridabadFaridabad	172172
IndiaIndia	VaranasiVaranasi	151151
IndiaIndia	GayaGaya	149149
IndiaIndia	PatnaPatna	144144
IndiaIndia	DelhiDelhi	143143

IndiaIndia	LucknowLucknow	138138
CameroonCameroon	BamendaBamenda	132132
IndiaIndia	AgraAgra	131131
IndiaIndia	MuzaffarpurMuzaffarpur	120120
IndiaIndia	SrinagarSrinagar	113113
IndiaIndia	GurgaonGurgaon	113113

World Health Organization

   Technically, the WHO doesn’t treat its data as a ranking but rather a measurement of where risks are higher. But it’s clear from the report that India is one of the riskiest countries in the world to breathe, up there with Bangladesh and Georgia. When it comes to comparing PM10 measurements of the world’s largest cities, India’s capital Delhi comes in with an annual average of 292, ahead of Cairo (284), Dhaka (147), Mumbai (104), and Beijing (92), the Washington Post noted.

Q.(1)List any four reasons for poor air quality index in so many cities in India?

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(2) What do you mean by PM as mentioned above in PM 2.5 and PM 10-

A.      Pollution Meter

B.      Particulate Matter

C.      Performance Monitor

D.     Particular Material

(3) The lungs of a person living in Shimla and that living in Delhi were compared by Dr.VivekGoyal. He noticed that the lungs of person living in Shimla were pinkish red but that of person living in Delhi for last ten years was black. Explain the cause of such difference in your own words?

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(4) From the data given above, write names of any two cities that have PM 2.5 more than 170?

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(5)Carbon-di-oxide is very important gas for maintaining the temperature of the earth. It is also needed by plants for photosynthesis. Even though it is now being considered as a pollutant. Comment

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Answer- key

(1) Full credit: Increased use of vehicles

Burning farm waste.

Industrial pollution and smoke.

Too much construction.

Partial Credit: Any three correct responses

No Credit: Any other response or no response

(2) Full Credit: Particulate matter

 No Credit: Other response or missing response

(3) Full Credit: Delhi is a polluted city, so the person’s lungs are being badly affected by the pollutants and on the other hand Shimla is a hill station with clean fresh air. So, the lungs of the person living in Shimla are pinkish red.

No Credit: No response or other response

(4) Full Credit: Kanpur and Faridabad

No Credit: No response or other response

(5) Full Credit:The level of Carbon di oxide in the atmosphere is increasing day by day by

different human activities. It traps sun rays when reflected from earth. But more CO 2 is causing global warming and changing earth’s climate.

No Credit: No response or other response

s-block elements slide presentation part-1

 It is the slide presentation on s-block elements- ppt for class 11

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Acids,bases and salts -important questions with answer

 CHAPTER 2 ACIDS, BASES AND SALTS

1.        A sample of soil is mixed with water and allowed to settle. The clear supernatant solution turns the pH paper yellowish-orange. Which of the following would change the colour of this pH paper greenish-blue?

(i)  Lemon juice

(ii)  vinegar

(iii)  common salt

(iv)  antacid

2.        Which of the following salt does not contain water of crystallization?

(i)  Blue vitriol

(ii)  Baking soda

(iii)  Washing soda

(iv)  Gypsum

FILL IN THE BLANKS

3.                       is a natural indicator whereas        is a synthetic indicator.

4.        The acid and base present in sodium acetate are and respectively.

5.                             is called king of chemicals.

     ONE MARK QUESTIONS

6.        Name the substance obtained by the action of chlorine on dry slaked lime.

7.        In addition to sodium hydrogen carbonate baking powder contains a substance X. Name the substance X.

8.        How many molecules of water of crystallization are present in washing soda and POP

ASSERTIONS AND REASONS

For the question numbers 10, 11 and 12, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and

(d) as given below:

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

9.        Assertion: Baking powder is used in making cake instead of using baking soda.

 Reason: Baking powder contains tartaric acid which reacts with sodium carbonate and removes bitter taste.

10.     Assertion: Pure water is neither acidic nor basic.

       Reason:The pH of a solution is inversely proportional to the concentration of hydrogen ions in it.

11.     Assertion: The aqueous solution of glucose and alcohol does not show acidic character. 

    Reason: Aqueous solutions of glucose and alcohol do not produce hydrogen ions. 

THREE MARK QUESTIONS

12.     How can you prepare sodium hydroxide? Name the products formed on cathode and anode. Write one use of each by-product formed in the above reaction.

13.     A substance X is used as a building material and is insoluble in water. When reacted with dilute HCl, it produces a gas that turns lime-water milky. Predict the substance and write the chemical equations involved

14.      Give a reason for the following :

(i)  Ammonia is a base but does not contain a hydroxyl group.

(ii)  Milk  of Magnesia is used by  a person suffering  from acidity.

(iii)  Sodium hydroxide cannot be kept in aluminium containers.

15.      (a) Write an equation for the reaction of iron with steam. Name the compound of iron obtained

  (b)A small amount of copper oxide is taken in a beaker and dil. HCl is added slowly while stirring

(i)  What is the colour of the solution obtained?

(ii)  What happens to copper oxide during the reaction?

FIVE MARK QUESTION

16.       (a) A liquid has a pH less than 7 which represents an acidic solution.

(i)  State the nature of the solution, if its pH increases from 7 to 14.

(ii)  Mention the ion whose concentration increases with the increase in pH value.

(iii)  Suggest a method that is generally used for measuring pH value.

(b)A student collected two samples of dil HCl and distilled water in  a  separate test  tube.   She  forgot to label the tubes. Both samples are colourless. The solution of litmus, phenolphthalein and lime water is available to her.

(i)  How will she distinguish between the two samples?

17.       (i) What is the chemical name of the Plaster of Paris?

(ii)  Write the chemical formula of plaster of Paris in two ways.

(iii)  What happens when Plaster of Paris comes in contact with moisture? Also support your answer with the help of chemical equation.

(iv)  Write the two uses of the Plaster of Paris.

18.        Demonstrate with the help of an experiment how acidic solution conducts electricity.

(i)  If acetic acid and hydrochloric acid of the same concentration are taken, which of the two is stronger acid and why?

(ii)  How the strength of alkali solution is will be affected if sodium hydroxide added to it?

19.       CASE- STUDY

Answer question numbers 20(a) to 20(d) based on your understanding of the following paragraph and the related studied concepts.

Sunita was learning to bake cakes. She added the ingredients according to the recipes and placed them in the oven. When the cake was ready she took it out from the oven. She was surprised as the cake was hard instead of soft and fluffy.

(a) What is the probable reason that the cake was not fluffy?

(b)   What ingredient did she miss adding while preparing the cake?

(c) Write a chemical reaction to show how this ingredient makes the cake fluffy? 

(d)What is the chemical constituent of this ingredient?