WBBSE Class 10 Physical Science Notes Chapter 1 Concerns About Our Environment | WBBSE Class 10 Physical Science Solutions Chapter 1 Notes in ENGLISH
WBBSE Class 10 Physical Science Chapter 1 Question Answer – Concerns About Our Environment
**Question 1.**
**In which atmospheric layers does temperature increase with altitude?**
**Answer:**
Temperature increases with altitude in the Stratosphere and Thermosphere.
**Question 2.**
**Which is more harmful to the human body – CO or CO2?**
**Answer:**
CO (Carbon Monoxide) is more harmful to the human body.
**Question 3.**
**In which layers of the atmosphere does temperature decrease with altitude?**
**Answer:**
Temperature decreases with altitude in the Troposphere and Mesosphere.
**Question 4.**
**What is the temperature range of the atmosphere?**
**Answer:**
The temperature range of the atmosphere spans from -92°C to +1200°C.
**Question 5.**
**What is the primary source of carbon monoxide in the atmosphere?**
**Answer:**
Coal, petrol, and incomplete combustion of other fossil fuels contribute to the presence of carbon monoxide in the atmosphere.
**Question 6.**
**In which atmospheric layer is the maximum concentration of ozone found?**
**Answer:**
The Stratosphere contains the highest concentration of ozone.
**Question 7.**
**Name some gases responsible for the greenhouse effect.**
**Answer:**
Carbon dioxide (CO2), methane (CH4), water vapor (H2O), chlorofluorocarbons (CFC), and nitrous oxide (N2O) contribute to the greenhouse effect.
**Question 8.**
**What are the sources of dissolved oxygen in water?**
**Answer:**
Dissolved oxygen in water originates from atmospheric oxygen and the photosynthesis carried out by aquatic plants during daylight.
**Question 9.**
**Name the main compounds causing damage to the ozone layer.**
**Answer:**
Nitric oxide (NO) and Freons are the primary compounds causing damage to the ozone layer.
**Question 10.**
**What compound is formed when CO gas combines with blood?**
**Answer:**
Carboxyhemoglobin is formed when carbon monoxide (CO) gas combines with blood.
**Question 11.**
**Which disease is caused due to the formation of a hole in the ozone layer, and why?**
**Answer:**
The formation of a hole in the ozone layer allows ultraviolet rays from the sun to reach the Earth, causing skin cancer.
**Question 12.**
**Name some waste management methods.**
**Answer:**
Waste management methods include burning and incineration, recycling processes, sewage treatment, and dumping.
**Question 13.**
**Name some methods used in green chemistry.**
**Answer:**
Green chemistry methods involve the use of sunlight, microwaves, sound waves, and enzymes.
**Question 14.**
**What is COD?**
**Answer:**
COD stands for Chemical Oxygen Demand.
**Question 15.**
**Name two sinks of carbon dioxide.**
**Answer:**
The ocean, where carbon dioxide dissolves, and plants, which utilize it for photosynthesis, serve as sinks for carbon dioxide.
**Question 16.**
**Which type of pollution affects sea birds?**
**Answer:**
Oil pollution adversely affects sea birds.
**Question 17.**
**What are the main sources of thermal pollution?**
**Answer:**
Nuclear plants and thermal power plants are the primary sources of thermal pollution.
**Question 18.**
**What is siltation?**
**Answer:**
Siltation is the mixing of soil or rock particles into water.
**Question 19.**
**Which gas was responsible for many deaths in the Bhopal tragedy?**
**Answer:**
The gas methyl isocyanate (MIC) was responsible for numerous deaths in the Bhopal tragedy.
**Question 20.**
**What type of aromatic compounds are present as particulates in the air?**
**Answer:**
Polycyclic aromatic hydrocarbons (PAH) are present as particulates in the air.
**Question 21.**
**What are silicosis and asbestosis?**
**Answer:**
Silicosis is a lung disease caused by silica particulates, while asbestosis is caused by asbestos particulates.
**Question 22.**
**Which class of people is generally susceptible to black lung and white lung diseases?**
**Answer:**
Workers in coal mines and cotton mills are generally susceptible to black lung and white lung diseases, respectively.
**Question 23.**
**What is PCB?**
**Answer:**
PCB stands for polychlorinated biphenyl, a highly toxic compound.
**Question 24.**
**Why does the fish population get hindered in thermally polluted water?**
**Answer:**
Thermal pollution increases water temperature, decreasing the dissolved oxygen level and adversely affecting fish growth.
**Question 25.**
**What is chlorosis?**
**Answer:**
Chlorosis is the phenomenon where the presence of SOx pollutants in the atmosphere slows down chlorophyll production in plant leaves, causing the green color to disappear.
**Question 26.**
**Why do high and low tides occur in the sea?**
**Answer:**
High and low tides in the sea occur due to the gravitational pull of the sun and moon on the Earth, causing variations in water levels.
**Question 27.**
**To what form of energy is tidal energy converted for use?**
**Answer:**
Tidal energy is converted to electrical energy for use.
**Question 28.**
**Where in the world is geothermal energy used to generate electricity?**
**Answer:**
Geothermal energy is used to generate electricity in regions where molten hot rocks are formed due to geological changes.
**Question 29.**
**What are petro-crops?**
**Answer:**
Petro-crops are plants, like Euphorbias, that contain latex with high carbon content. The thermal cracking of this latex produces bio-petrol or diesel.
**Question 30.**
**What is the name of anaerobic bacteria used for the fermentation of biomass?**
**Answer:**
Methanogenic bacteria are used for the anaerobic fermentation of biomass.
**Short Answer Type Questions:**
**Question 1.**
**What are combustible and non-combustible materials?**
**Answer:**
Combustible materials are those that can be burnt, while non-combustible materials cannot be burnt.
**Question 2.**
**What are the types of sources of energy?**
**Answer:**
There are two types of sources of energy: renewable sources and non-renewable sources.
**Question 3.**
**What is nuclear fission?**
**Answer:**
Nuclear fission is a process in which a heavier nucleus splits into lighter nuclei with the release of significant energy.
**Question 4.**
**What is petroleum? What is natural gas?**
**Answer:**
Petroleum is a complex mixture of hydrocarbons derived from rocks, while natural gas is a fossil fuel found above petroleum beneath the Earth's surface.
**Question 5.**
**What is destructive distillation?**
**Answer:**
Destructive distillation is the process of burning wood in a limited supply of oxygen.
**Question 6.**
**What is a hydroelectric power plant?**
**Answer:**
A hydroelectric power plant utilizes the energy of flowing water to produce electricity on a large scale.
**Question 7.**
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**Question 10.**
**What are the disadvantages of fossil fuels?**
**Answer:**
Disadvantages of fossil fuels include:
1. **Non-renewable:** Fossil fuels are finite resources and cannot be replenished on human timescales.
2. **Air Pollution:** Burning fossil fuels releases air pollutants, contributing to environmental pollution.
**Question 11.**
**What is geothermal energy?**
**Answer:**
**Geothermal energy:** This is the energy harnessed from the heat inside the Earth. It involves tapping into the Earth's internal heat for various applications.
**Question 12.**
**If you could use any source of energy for heating your food, which one would you use and why?**
**Answer:**
**LPG (liquefied Petroleum Gas):** It is chosen for heating food because it is readily available in kitchens, produces no smoke on burning, and is efficient in terms of cooking time.
**Question 13.**
**Name two energy sources that you would consider to be renewable. Give reasons for your choice.**
**Answer:**
**Solar energy and wind energy:** These are renewable sources as they are replenished quickly by natural processes.
**Question 14.**
**Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choice.**
**Answer:**
**Coal and petroleum:** These are exhaustible sources because their stock is depleting, and their formation takes millions of years.
**Question 15.**
**Fish do not grow as well in warm water as in cold water-explain why.**
**Answer:**
**Explanation:** Warm water holds less dissolved oxygen than cold water. As oxygen is crucial for fish respiration and growth, fish tend to grow less efficiently in warm water.
**Question 16.**
**What is chlorosis?**
**Answer:**
**Chlorosis:** It's the process where sulfur dioxide (SOx) in the atmosphere hinders chlorophyll production in plant leaves, causing the green color to disappear.
**Question 17.**
**What is siltation?**
**Answer:**
**Siltation:** This is the process of mixing soil particles with water. It increases water turbidity, hindering the free movement of aquatic organisms and reducing their growth and productivity.
**Question 18.**
**In which season does the depletion of the ozone layer in Antarctica take place, and when is it filled up again?**
**Answer:**
During spring in Antarctica, i.e., in September and October, the depletion of the ozone layer occurs. However, after spring, in November and December, the produced ozone hole is filled up.
**Question 19.**
**What is meant by inversion temperature in different regions of the atmosphere?**
**Answer:**
**Inversion temperature:** As we move from one region of the atmosphere to the next higher region, the temperature trend changes either from increase to decrease or from decrease to increase. This trend is called inversion temperature.
**Question 20.**
**How does a carbon monoxide molecule link to a hemoglobin molecule?**
**Answer:**
**Explanation:** In a hemoglobin molecule, the Fe(II) atom is linked to five groups by coordinate bonds, leaving the sixth site free. In the presence of both carbon monoxide (CO) and oxygen (O2), CO, being a stronger ligand, occupies the vacant coordination site in hemoglobin instead of oxygen.
**Brainstorming Questions: Very Short Answer Type Questions:**
**Question 1.**
**In which layer of the atmosphere is the least temperature found?**
**Answer:**
Mesopause, the upper part of the mesosphere, has the least temperature, around -85°C.
**Question 2.**
**Why is the ionosphere so called?**
**Answer:**
The ionosphere is so-called because it contains ions and electrons produced due to ionization reactions in the presence of high-energy solar UV radiation.
**Question 3.**
**What is a 'moisture trap,' and why is it called so?**
**Answer:**
The tropopause is called a 'moisture trap' because most water vapor in the stratosphere enters through the tropopause due to its low temperature, leaving the stratosphere dry.
**Question 4.**
**What is an ozone hole?**
**Answer:**
An ozone hole is a region of exceptionally depleted ozone in the stratosphere, mainly over Antarctica, attributed to the chemical action of CFCs and other atmospheric pollutants, resulting in increased ultraviolet rays at ground level and an elevated risk of skin cancer.
**Question 5.**
**What do you mean by ODS?**
**Answer:**
ODS stands for Ozone-Depleting Substances. These are chemical substances that catalyze and accelerate the depletion of ozone, including Chlorofluorocarbons (CFCs) and Halons.
**Question 6.**
**What is the Dobson unit (DU)?**
**Answer:**
The Dobson unit (DU) is a unit of measurement for the columnar density of a trace gas in the Earth's atmosphere, often used for measuring ozone concentration.
**Question 7.**
**Why is global warming a consequence of the greenhouse effect?**
**Answer:**
Global warming is a consequence of the greenhouse effect because greenhouse gases trap heat in the Earth's atmosphere, leading to a rise in average global temperatures.
**Question 8.**
**Which compound has approximately 20 times more greenhouse effect than carbon dioxide?**
**Answer:**
Methane (CH4) has approximately 20 times more greenhouse effect than carbon dioxide (CO2).
**Question 9.**
**What is a greenhouse?**
**Answer:**
A greenhouse is a glass house used for growing plants, vegetables, fruits, and flowers in colder regions where outdoor cultivation is challenging due to low temperatures.
**Question 10.**
**Is the greenhouse effect applicable only to Earth?**
**Answer:**
No, the greenhouse effect is not exclusive to Earth. In the solar system, the atmospheres of Venus, Mars, and Titan also contain gases that cause a greenhouse effect.
**Question 11.**
**Name two radiations emitted by the sun that are not visible to the human eye.**
**Answer:**
Infrared radiation and ultraviolet radiation are not visible to the human eye.
**Question 12.**
**Which one is the principal greenhouse gas?**
**Answer:**
Apart from water vapor, carbon dioxide (CO2) is considered the principal greenhouse gas when ranked by its direct contribution to the greenhouse effect.
**Question 13.**
**Name a non-renewable source of energy other than fossil fuels.**
**Answer:**
Nuclear energy is a non-renewable source of energy other than fossil fuels.
**Question 14.**
**What is the empirical formula of methane hydrate?**
**Answer:**
The empirical formula of methane hydrate is (CH4)4 · (H2O)23.
**Question 15.**
**Which process is the basis for the formation of biomass?**
**Answer:**
Photosynthesis is the fundamental process for the formation of biomass.
**Question 16.**
**Which country generates the maximum electricity using wind energy?**
**Answer:**
Germany produces the maximum electricity using wind energy.
**Question 17.**
**What should be the maximum wind speed to operate a
