Environmental Sanitation MCQ Quiz in मल्याळम - Objective Question with Answer for Environmental Sanitation - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക

The correct answer is All of the above.

Concept:

• A large number of diseases are caused by poor sanitation and contaminated drinking water.
• Human excreta control, solid waste and wastewater management, and pest and vector control are all aspects of environmental sanitation.
• Untreated human excreta is a health hazard.
• It has the potential to pollute both water and soil.
• Pollution affects both surface and groundwater. Wells, tube-wells, springs, and many rivers get their water from groundwater.
• Adopting good sanitation practises should be a way of life for all of us.

Explanation:

Environmental sanitation includes

Community sanitation:

• Community sanitation is the collaborative effort to improve the health and disease prevention of a group of individuals who live close to one another.

Domestic sanitation:

• Domestic sanitation, which includes hygienic food preparation, cleaning, and ventilation, refers to the cleanliness of your home.

Personal sanitation:

• Personal sanitation, which includes healthy living habits, cleanliness of the body and clothing, a nutritious diet, and a well-balanced schedule of rest and exercise, refers to the cleanliness of your person or body.

The correct answer is 7.

• Chlorination is a chemical disinfection method that uses various types of chlorine or chlorine-containing substances for the oxidation and disinfection of what will be the potable water source.

Key Points

• Chlorine, whether in the form of pure chlorine gas from a cylinder, sodium hypochlorite, or calcium hypochlorite in any of its presentations, dissolves in water to form hypochlorous and hydrochloric acids.
• A pH between 6.5 and 8.5 will see both hypochlorous acid and hypochlorite ions present in the water.
• Together, the hypochlorous acid and the hypochlorite ions are referred to as free chlorine.
• Hypochlorous acid is the more effective disinfectant, and therefore, a lower pH is preferred for disinfection.
• Calcium hypochlorite (CaOCl) is made up of the calcium salts of hypochlorous acid. It is produced by dissolving chlorine gas (Cl₂) into a solution of calcium oxide (CaO) and sodium hydroxide (NaOH).
• Sodium hypochlorite (NaOCl) is made up of the sodium salts of hypochlorous acid and is a chlorine-containing compound that can be used as a disinfectant. It is produced when chlorine gas is dissolved into a sodium hydroxide solution.
• The reaction of chlorine in water follows the reaction shown below:
  • Cl₂ + H₂0 →HOCl + HCl
  • Hydrochloric acid dissociates in turn to form hydrogen and chloride ions HCl → H⁺ + Cl^-
  • Hypochlorous acid however dissociates only partially HOCl ⇔ H⁺ + OCl^-

Key Points

• Water is called the "universal solvent" because it is capable of dissolving more substances than any other liquid.
• This is important to every living thing on earth.
• This allows the water molecule to become attracted to many other different types of molecules.
• Water has no definite shape.
• It is tasteless.
• It is odourless.
• It is colourless.
• Any colour present in water is due to the presence of dissolved or suspended impurities in it.
• Materials like air, water, and clear glass are called transparent.
• When light encounters transparent materials, almost all of it passes directly through them. 
• Pure water (solely hydrogen and oxygen atoms) has a neutral pH of 7, which is neither acidic nor basic.
• Water should be free from nitrogen organic matter.
• Density: 997 kg/m³
• Boiling point: 212°F (100°C)
• Molar mass: 18.01528 g/mol
• Melting point: 32°F (0°C)
• Formula: H2O
• IUPAC ID: Water, Oxidant

Thus, all of the above are the main properties of water.

• The hardness of water is that characteristic that prevents the formation of sufficient leather or foam.
• It occurs due to the presence of carbonates, bicarbonates, sulphates, chlorides of calcium and magnesium(Ca and Mg).
• The hardness of water is due to the presence of dissolved minerals of Ca2+, Mg2+, Al3+, Iron and other heavy elements. Specifically due to Calcium Sulphate, Calcium Bicarbonate, Calcium chloride, Magnesium Sulphate, Magnesium Bicarbonate and Magnesium chloride.​

Key Points 

Temporary hardness (Carbonate hardness):

• Temporary hardness is caused by the presence of dissolved bicarbonates of Calcium (Ca(HCO3)2 ), Magnesium (Mg(HCO3)2 ), Iron and other heavy elements.
• It can be eliminated by mere boiling.

Ca(HCO3)2 → CaCO3↓ + H2O + CO2 ↑

Mg(HCO3)2 → MgCO3 + H2O + CO2 ↑

MgCO3 → Mg(OH)2↓ + CO2 ↑

Permanent Hardness (non-carbonate hardness):

• Permanent Hardness is due to the presence of dissolved chlorides and sulphates of Calcium, Magnesium, Iron and other heavy elements.
• It cannot be eliminated by boiling.

Hence, we can conclude that Magnesium sulfate is responsible for the permanent hardness of the water.

Additional Information

Degree of Hardness:

• The degree of hardness is the extent of hardness.
• It is expressed as weight in milligrams of CaCO3 equivalent to all hardness causing substances in one million milligrams of water. That is parts per million (ppm). Or it can be expressed as weight in milligrams of CaCO3 equivalent to all hardness causing substances in one litre of water.​

CaCO3 as reference for Hardness:

• CaCO3 is stable, non-hygroscopic and is obtained in pure form. Therefore a standard hard water solution can be prepared by dissolving accurately weighed CaCO3 in dilute HCl and make up to a known volume.
• CaCO3 is insoluble in water. Therefore it can be easily precipitated in water treatments.
• Molecular weight of CaCO3 is 100, so mathematical calculations are easy

Concept:

• Rainwater is the purest form of natural water.
• It is also one of the major sources of water.

Explanation:

Rainwater:

• Rainwater is the purest and natural source of water because it is produced by the condensation of water in presence of the sun.
• The water is directly coming from the evaporation of freshwater of ponds, rivers, lakes, etc.
• It does not contain any kind of impurities.
• Because of the natural process of vaporization, all impurities get removed.
• It is generally used in labs because of its purity.
• Rainwater is harvested in various places and used as drinking water.

Thus, rainwater is the purest and best.

Additional InformationWater of well: 

• It is a traditional source of water.
• Water is drawn up by bucket from the well to use.
• It is one of the oldest methods.
• The water of the well is used for various purposes such as drinking and irrigation, etc.
• Underground water of some places is contaminated with arsenic, lead or chromium. 

Ocean water:

• It is the largest source of water.
• It covers 70 per cent of surface water on the earth.
• The water of the ocean is salty in nature.
• It is not safe water to drink.
• Ocean water is polluted due to the dumping of waste and polluted water from the rivers.

River water

• It is natural flowing water.
• It flows from downhill to the ocean.
• It is home to various species of fish, frogs, crocodiles, etc.
• It is also a source of canal water which is used by farmers for irrigation.
• River water is the most polluted source of surface water due to human usage and effluent discharge.

Key Points

• The hardness of water is due to the presence of soluble bicarbonates, chlorides, and sulfates of calcium and magnesium. 
• Water is the most important compound that is needed for the survival of life on earth.
• Water is present in the oceans, rivers, ponds, lakes, glaciers. etc.
• Rainwater is considered pure water because it does not contain any salt dissolved in it.

Important Points

The hardness of water can be classified into two types:

Temporary Hardness-

• It occurs due to the presence of magnesium and calcium carbonates in the water.

Permanent Hardness-

• It occurs when soluble salts of magnesium and calcium are present in the form of chlorides and sulfides in water.

​Thus, calcium salts are dissolved in hard water.

Additional Information 

Calcium Salts

• Calcium salts are used as a source of calcium, an essential nutrient cation.
• Calcium salts are used as a source of calcium cation for the treatment or prevention of calcium depletion when dietary measures are inadequate.

• Pollution occurs when a substance present in the environment prevents the functioning of natural processes and produces harmful environmental and health effects.
• In the natural world, many substances accumulating in the environment are processed through the intricate network of biogeochemical cycles.

Key Points

Blue baby Syndrome/Methemoglobinemia (MetHb): 

• It is caused by the decreased ability of blood to carry oxygen, resulting in oxygen deficiency in different body parts.
• Infants are more susceptible than adults.
• It is a blood disorder that can lead to an abnormal amount of methemoglobin being produced.
• With methemoglobinemia, the haemoglobin can carry oxygen but is not able to deliver it effectively to body tissues.
• It can potentially cause more serious symptoms due to insufficient oxygen.
• The disease can be caused by intake of water and vegetables high in nitrate, exposure to chemicals containing nitrate or can even be hereditary.
• Infants who drink water with high levels of nitrate (or eat foods made with nitrate-contaminated water) may develop a serious health condition due to the lack of oxygen.
• They show signs of blueness around the mouth, hands and feet and hence the name “Blue baby syndrome”.

Thus, Blue-baby syndrome is caused by water pollution.

Additional Information

The correct answer is Landfill.

Explanation:

• Wastes from homes, schools, offices, hospitals, etc., that are collected and disposed of by the municipality generally consist of paper, leather, textile, glass, rubber, etc.
• A landfill is an area where garbage from a city or town is disposed off.
• Wastes are dumped in a depression or trench after compaction and covered with dirt. 
• When a landfill is completely full, it is usually converted into a park or a play area.
• No new buildings will be built on it for the next 20 years or so.
• But seepage of chemicals from these landfills can pollute underground water resources.

Important PointsWater Bodies:

• Humans have been abusing water bodies (ocean, sea, river, etc) all over the world by disposing of various types of waste into them.
• This is not the preferred waste disposal method.
• When waste is dumped in the water body the waste in the pond starts to decompose at a rapid rate.
• This decomposition process leads to the depletion of oxygen in the water body.
• When the dissolved oxygen present in the water decreases the fishes die.

Key Points

The Forest (Conservation) Act:

• The Forest (Conservation) Act 1980 was passed to provide for the conservation of forests and for matters connected therewith or ancillary or incidental thereto.
• Under the provisions of this Act, prior approval of the Central Government is required for the diversion of forestlands for non-forest purposes.
• The Forest (Conservation) Act 1980 was further amended in 1988.
• The Forest Conservation Act was enacted on 25 October 1980.
• It provides the conservation of forests and matters connected to the habitat of many animals as well.
• The aim of the Forest (Conservation) Act was to ensure the protection and conservation of trees so that they can support the wildlife as well as save the habitat of many animals and keep an eye on the deforestation and degradation of forest resources.
• It extends to the whole of India except the State of Jammu and Kashmir.

Thus, the Forest Conservation Act was passed in the year 1980.

• Composting is the natural process of decomposition and recycling of organic material into a humus-rich soil amendment known as compost.
• For any business or institution producing food waste, this organic material can be easily decomposed into high-quality compost.

Key Points

• Mature or stable compost is similar to humus in appearance, smell, and touch.
• The finished compost will no longer heat on its own, thus maintaining the ambient temperature, and there will be no weed seeds or pathogens.
• Compost can be used to increase pasture quality in intensively managed grazing systems.
• It is estimated that 1 ton of organic waste can be converted into manure in 24 hours.

​Hence, 1 ton of organic waste can be converted into manure in 24 hours.