Chemicals Used in Daily Life
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Lesson – 19.
Chemicals used in Daily life.
Exercise.
2) Difference between.
(a) Chemical pesticide and Biological pesticide
| Chemical pesticide | Biological pesticide |
|---|---|
| They do not decompose easily. | They decompose easily in environment. |
| They are made from various chemicals which are harmful to our environment. | They are made from natural organisms or substances which are derived from natural organisms. |
| For eg: DDT, Aldrin. | For eg: NPV, sugar derived. |
(b) Chemical food preservative and Organic food preservative
| Chemical food preservative | Organic food preservative |
|---|---|
| They are artificially produced. | They are obtained from natural methods and items. |
| They are non-biodegradable. | They are bio degradable. |
| For eg: BHA, BHT. | For eg: Sugar, Salt, keeping in cold place. |
(c) Soap and Detergent
| Soap | Detergent |
|---|---|
| It’s less effective in hard water. | It’s more effective in hard water. |
| They are environmental friendly. | They causes water pollution and they are not environmental friendly. |
| They are used for personal hygiene. | They are used for laundry purposes. |
3) Give reason.
(a) Use of DDT powder cause imbalance in the ecosystem.
Answer: Because it is a persistent organic pollutant that accumulates in the environment and food chain causing imbalance in ecosystem.
(b) The use of chemical pesticides should be decreased.
Answer: Because they are non-bio degradable in air our health and causes soil pollution, water pollution etc.
(c) Salt is used in the process of making soap.
Answer: Because salt helps to separate soap from the mixture.
(d) Pickles can be preserved for a long time.
Answer: Because in pickles certain methods of preserving are applied and salt which helps it to get preserved for a long time.
4) Answer the following questions:
(a) Write the full form of DDT and BHC.
Answer: DDT → Dichloro Diphenyl Trichloroethane.
BHC →
(b) What do you mean by food preservatives? Why are they used?
Answer: The substance used to protect food from decaying are called food preservatives. They are used to prevent food from decaying for a long time.
(c) What chemicals are used as food preservatives?
Answer: The chemicals used as food preservatives are:
- sodium benzoate.
- benzoic acid.
- sulphur dioxide.
(d) What are the natural methods used to preserve the nutrients in food?
Answer: The natural methods used to preserve the nutrients in food are:
- Drying in sun.
- use of wood ash.
- mixing of turmeric and oil.
(e) What do you mean by natural food preservatives? Why are they good in comparison to the chemical food preservatives? Analyze it.
Answer: The preservatives that come from organic matter and are used to protect natural food from decaying are known as natural food preservatives. They are good in comparison to the chemical food preservatives because they do not have any side effect and are naturally available than the chemical does.
(f) How can fruits be ripened artificially?
Answer: The methods for ripening fruits are as follows:
Fruits can be ripened artificially by using different ripening agents like calcium carbide, ethylene gas, ethephon etc.
The chemical methods for fruit ripening using calcium carbide process are as follows:
- place the fruits in a sealed container or bag.
(e) What do you mean by natural food preservatives? Why are they good in comparison to the chemical food preservatives? Analyze it.
Answer: The preservatives that come from organic matter and are used to protect natural food from decaying are known as natural food preservatives. They are good in comparison to the chemical food preservatives because they do not have any side effect and are naturally available than the chemical does.
(f) How can fruits be ripened artificially?
Answer: The methods for ripening fruits are as follows:
Fruits can be ripened artificially by using different ripening agents like calcium carbide, ethylene gas, ethephon etc.
The chemical methods for fruit ripening using calcium carbide process are as follows:
- place the fruits in a sealed container or bag.
- Add small quantity of calcium carbide wrapped in paper cloth and direct contact with fruits.
- Seal the containers or bag and leave at room temperature for 24-48 hours.
- Ensure proper ventilation during and after the ripening process to dissipate acetylene gas.
(g) What precautions should be taken while using chemical pesticides?
Answer: Precautions:
- The pesticides should be stored in an air tight container in proper place.
- protective suits should be used while using pesticides.
- Only less harmful but effective pesticides should be used.
- The utensils used for spraying pesticides should be cleaned immediately after the use and stored in a safe place.
- We should wash our hands and take a bath immediately after spraying pesticides.
(h) Make a list of chemicals used for cleaning purpose in your house and locality. Write the effect of those substances in the environment.
Answer: The chemicals that are used for cleaning purpose are:
- Soap
- Detergent
- Harpic
- Phenol
Their effects are:
- It causes water pollution.
- They contain harmful agents cause several health issues.
- Bleach and can harm soil.
- Excessive use of chemical causes soil pollution, water pollution.
(i) Explain soap making process.
Answer: The soap making process are as follows:
- Take animal oil and vegetable oil in a beaker.
- make about 80ml mixture of sodium hydroxide by dissolving 15 grams of sodium hydroxide in 50 ml water.
- mix both solution and heat the mixture on the flame for some time. It forms a thick paste. Add a little soda and common salt. The salt helps to separate soap from the mixture.
- now filter the mixture by using a filter paper. The residue left on the filter paper is raw soap. Now pour the soap in a desired shape vessel.
- keep the soap undisturbed for a day and now solidify it in soap of desired shape. The remaining solution of the filtrate contains glycerine.
(j) What is detergent? Write its two effects on each of the human health and environment due to the use of detergent present your opinion.
Answer: Detergent is a chemical obtained from hydrocarbon which is more soluble in water than soap and used in clean clothes.
Its two effects in human health and environment are:
- It cause problem like skin irritation or skin burn.
- It can fade the color of clothes.
- It causes soil and water pollution.
- It is non-biodegradable and cause chemical pollution.
(k) There may be an excessive use of chemicals in agriculture for their uplifting development complex problems have been observed on the health of people and the environment. What measures could be taken to solve these problems? Write some suggestions.
Answer: I will suggest the following points to the people to solve these problems:
- Only less harmful and less effective pesticides should be used.
- While using them full body cover suits should be used.
- Utensils should be cleaned properly after using pesticides but not near the water sources.
- People should wash and immediately take bath after using pesticides.
- Vegetable and crops should not be consumed directly after using the pesticides.
(l) What do you mean by chemical pollution? What are its effects on the protection of the environment?
Answer: Chemical pollution refers to the release of harmful chemicals into the environment where they can cause damage to ecosystem.
Its effects are:
- It’s cause respiratory issues.
- It causes ocean pollution.
- It is the cause of soil degradation.
- chemical pollution destroy natural habitat and organisms live there.
The measures to minimize it are:
- Harmful chemicals like (BHC) should be banned.
- proper disposal system should be established.
- Eco-friendly Agriculture should be promoted.
- Awareness program related to chemical pollution should be done.
(m) Write about the pollution caused by industrial products like cement, glass, ceramics, plastic, rubber, chemical fertilizers, soap, detergent in your locality. Write its causes and suggest proper ways for management.
Answer: The causes of the pollution caused by industrial products are:
- Throwing waste.
- Ecological imbalance.
- Global warming.
- Soil pollution.
The ways to minimize it are:
- Waste from Industries should be converted into products.
- Restraining the use of chemicals.
- By not throwing chemical waste to water bodies.
- Increase in afforestation.
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