Pollutants and Their Classification

Q.

What is meant by BOD and COD?

Q. Water is often treated with chlorine to

1. increase oxygen content
2. kill germs
3. remove suspended particles
4. remove hardness

Q.

Which of the following is responsible for polluting water?

1. Pathogens

2. Allergens

3. Hydrogen

4. None of the above

Q. Which of the following is a secondary pollutant?

1. $C{O}_2$
2. $N_{2}O$
3. $S{O}_2$
   
4. $PAN$

Q.

High value of biochemical oxygen demand (BOD) indicates that

1. Water is less polluted

2. Water is highly polluted

3. Water is pure

4. Consumption of organic matter in water is higher by the microbes

Q. Identify the pollutant gases which are responsible for the discolouration of marbles in the Taj Mahal.

1. $S{O}_{2}andN{O}_2$
2. $S{O}_{2}and{O}_3$
3. $C{H}_{4}andN{O}_2$
4. $O_{3}andC{O}_2$

Q. Addition of phosphates and nitrates/fertilizers into water leads to _________

1. Eutrophication
2. Increased growth of decomposers
3. Reduced algae growth
4. All of the above.

Q.

Which of the following come under the category of chemical pollutants?

1. Nickel

2. Cadmium

3. Mercury

4. All of the above

Q.

Explain the term pollutant.

Q. $1000\text{L}$ of air at STP was dissolved in water and it required $2.5\times {10}^{-5}$ moles of $KMn{O}_4$ for complete reaction with the pollutant $S{O}_2$. Thus, the $S{O}_2$ content in air is:

1. 1.4 ppm
2. 14 ppm
3. 2.8 ppm
4. 6.25 ppm

Q. Which of the following statement is not true? Reforestation will-

1. transpire more water vapour
2. cause more rain fall
3. increase pollution by particulate matter
4. raise the underground water level.

Q. If BOD of river is high, it means that the river is:

1. Not polluted
2. Very much polluted with inorganic chemicals
3. Very much polluted with organic chemicals which are decomposed by micro-organisms
4. Polluted with pesticides

Q.

Which of the following are the hallmarks of Green chemistry?

1. Minimal or no toxic waste

2. Preferably smaller energy footprint

3. Use of ambient temperatures

4. All of the above

Q.

Green chemistry means

1. Chemistry of chlorophyll

2. Chemistry of formation of starch in plants

3. Chemistry involving only non-toxic chemicals

4. Chemicals involving green coloured compounds

Q.

Pollution is not caused by

1. Thermal power plant

2. Automobile

3. Radioactive power plant

4. Hydrolytic power plant

Q. Which of the followings is incorrect? Addition of Phosphate containing fertilizers into water causes –

1. Decrease in amount of dissolved oxygen in water.
2. Eutrophication
3. Increase in fish population
4. Enhanced growth of algae

Q.

Which of the following reaction results in photochemical smog?

1. $N{O}_2\left(g\right)\underrightarrow{hv}NO\left(g\right)+O$

2. $NO\left(g\right)+O_3\to N{O}_2\left(g\right)+O_2\left(g\right)$

3. $Cl\left(g\right)+O_3\left(g\right)\to ClO\left(g\right)+O_2\left(g\right)$

4. Both (a) and (b)

Q. A water sample has ppm level concentration of follwing anions $F^{-}=10;S{O}_3^{2-}=100;N{O}_3^{-}=50$ the anion/ anions that make \ makes the water smaple unsuitable for drinking is / are :

1. only $N{O}_3^{-}$
2. both $S{O}_4^{2-}$ and $N{O}_3^{-}$
3. only $F^{-}$
4. only $S{O}_4^{2-}$

Q. Chief source of soil and water pollution is

1. agro industry
2. thermal power plant
3. mining
4. all of the above

Q. Which of the following is a viable particulate?

1. Algae
2. Smoke
3. Mist
4. Fumes

Q. Match column I with column II:
$\begin{array}{cc}\text{Column - I}& \text{Column - II}\\ \text{i.}Cr(OH{)}_3+H_2{O}_2\text{in basic medium}& \text{p.}CO+H_2\\ \text{ii. Acidic}KMn{O}_4+H_2{O}_2& \text{q.}N{H}_3\\ \text{iii.}C{a}_3{N}_2+H_{2}O& \text{r. Water-gas}\\ \text{iv. Red-hot coke + steam (at 1273 K, Ni catalyst)}& \text{s. Yellow solution}\\ & \text{t.}Ca(OH{)}_2\\ & \text{u. Solution decolourised}\end{array}$

1. $\text{(i-s), (ii-u), (iii-q, t), (iv-p, r)}$
2. $\text{(i-r), (ii-t), (iii-q, u), (iv-p, s)}$
3. $\text{(i-u), (ii-s), (iii-q, t), (iv-p, r)}$
4. $\text{(i-u), (ii-s), (iii-q, t), (iv-p, r)}$

Q. Ozone in the stratosphere is depleted by:

1. $C{F}_{2}C{l}_2$
2. $C_7{F}_{1}6$
3. $C_6{H}_{6}C{l}_6$
4. $C_6{F}_6$

Q. Biochemical Oxygen Demand, (BOD) is a measure of organic material present in water. BOD of less than 5 ppm indicates a water sample to be:

1. Rich in dissolved oxygen
2. Poor in dissolved oxygen
3. Highly polluted
4. Not suitable for aquatic life

Q. If BOD of river is high, it means that:

1. The river is not polluted
2. The river is very polluted
3. The river gets less light
4. The temperature is low