Air Pollution & Emissions

* Green hydrogen is any hydrogen that is produced from renewable energy. * Statement 1 is correct: Green hydrogen can be used as a direct fuel for internal combustion engines, replacing conventional fuels like gasoline or diesel. * Statement 2 is correct: Green hydrogen can be blended with natural gas and used as a fuel for various applications like heating, power generation, and industrial processes. * Statement 3 is correct: Green hydrogen can be used in hydrogen fuel cells to power electric vehicles, providing a clean and efficient alternative to traditional fossil fuel-powered vehicles. Therefore, all three statements regarding the uses of green hydrogen are correct.

Acid rain is primarily caused by the excess presence of nitrogen oxide and sulphur dioxide in the environment. * Carbon monoxide is not a direct cause of acid rain. It is a pollutant that contributes to the formation of ground-level ozone, but it does not lead to the production of acid rain. * Nitrogen oxides, which include nitric oxide and nitrogen dioxide, are major contributors to acid rain. When these gases react with water, oxygen, and other substances in the atmosphere, they form nitric acid, a key component of acid rain. * Ozone is not a direct cause of acid rain. While ozone can have negative environmental impacts, it is not a precursor to the formation of acid rain. * Sulphur dioxide is another primary contributor to acid rain. When Sulphur dioxide combines with water, oxygen, and other substances in the atmosphere, it forms sulphuric acid, which is also a major component of acid rain.

Statement 1 is correct. The WHO recommends that the 24-hour mean of PM2.5 should not exceed 15 ug/m³ and the annual mean should not exceed 5 ug/m³. These are the current most stringent guidelines set by WHO to protect public health. Statement 2 is incorrect. Ozone pollution typically peaks during sunny and stagnant weather conditions, not during inclement weather like rain or storms. Statement 3 is incorrect. While PM10 (≤ PM10) particles can enter the deep lungs and cause respiratory issues, it's the much finer PM2.5 (≤ PM2.5) particles and ultrafine particles that effectively penetrate the lung barrier (alveoli) to enter the bloodstream, affecting the heart, brain, and other organs. PM10 typically deposits in larger airways, whereas PM2.5's tiny size allows it to cross into the circulatory system, making it more dangerous.  Statement 4 is correct. Excessive ozone exposure can trigger asthma attacks and worsen respiratory problems. Ozone irritates the respiratory tract, making it harder to breathe.

System of Rice Intensification (SRI) includes a method called Alternate Wetting and Drying (AWD) which is a form of controlled irrigation of the rice crops. The benefits from the program include 1. Reduction in methane emissions as compared to traditional rice cultivation. 2. Reduction in water consumption . 3. Reducing fuel consumption . 4. Increase paddy yields . 5. Reduce required seeds for transplanting. 6. Reduce use of chemical fertilizers and agrichemicals . 7. Reduce irrigation demand . 8. Reduce production costs . 9. With increased output and reduced costs, farmers net income is increased .

Statement 1 is correct. PET fibres can be blended with cotton or wool to improve properties like wrinkle resistance and durability. Statement 2 is incorrect. Not all PET containers are suitable for all alcoholic beverages. Some PET can leach chemicals at high temperatures or with certain types of alcohol. It's important to check for specific suitability indicators on the packaging. Statement 3 is correct. PET bottles are one of the most commonly recycled plastics. They can be reprocessed into various products like clothing fibres, new bottles, or building materials. Statement 4 is incorrect. Incineration of PET, like most plastics, generates greenhouse gas emissions, including carbon dioxide. While PET has a lower emission profile compared to some other plastics, it's still not a zero-emission disposal method. Remember: Statements like store any kind of alcoholic beverages are vague & ambiguous, so they ought to be eliminated. Also, incineration of any substance cannot be environment friendly as it would definitely release GHGs. Hence the only Option left is Option A.
Therefore, the correct statements are 1 and 3.

The Common Carbon Metric (CCM) is a protocol developed by the United Nations Environment Program's Sustainable Buildings & Climate Initiative (UNEP-SBCI) for measuring energy use and reporting greenhouse gas (GHG) emissions from building operations. Its purpose is to support GHG emissions reductions through accurate measurement of energy efficiency. It is a universal method of measuring a building's carbon footprint and allows emissions from buildings around the world to be consistently assessed and compared. Therefore, it is used for assessing the carbon footprint of building operations around the world.

Statement 1 is correct. Furnace oil is indeed a product of oil refineries. It is a dark viscous residual fuel obtained by blending heavier components of crude oil. Statement 2 is correct. Furnace oil is widely used in industries like cement, steel, and textiles for power generation and heating. It is burned in boilers, furnaces, and engines to produce energy. Statement 3 is correct. Furnace oil contains high sulfur content, and its combustion releases sulfur oxides (SOₓ), contributing to air pollution and acid rain.

Magnetite particles, which are suspected to cause potential neurodegenerative problems, are generated as environmental pollutants from the following sources 1. Brakes of motor vehicles - The friction between brake pads and brake discs/drums can generate magnetite particles that are released into the environment. 2. Engines of motor vehicles - The high-temperature combustion processes in vehicle engines can also produce magnetite particles as a byproduct. 4. Power plants - The high-temperature industrial processes involved in power generation, such as coal-fired power plants, can lead to the release of magnetite particles into the environment. The other options (3. Microwave stoves within homes and 5. Telephone lines) are not major sources of magnetite particle pollution. Therefore, the correct answer is the combination of options 1, 2, and 4.

Statement 1 is Incorrect: While some carbon monoxide might be produced during the smelting process, it's unlikely to be in lethal quantities with proper emission controls. Statement 2 is Correct: Copper slag, a byproduct of the smelting process, can contain heavy metals like lead, arsenic, and cadmium. Rainwater or acidic runoff can leach these metals from the slag, contaminating soil and water resources. Statement 3 is Correct: Sulphur dioxide (SO2) is a major pollutant released during copper smelting, primarily from the burning of sulfur-containing fossil fuels used in the process. SO2 emissions contribute to acid rain and air pollution.

Statement 1 is correct: Zero tillage is a method of farming that involves sowing crop seeds directly into the soil without disturbing it. This method has several advantages.
In zero tillage, the residue of the previous crop is left on the field, which acts as a natural mulch, reducing soil erosion and improving soil fertility. Therefore, there is no need to burn the residue of the previous crop before sowing wheat. Statement 2 is correct: In zero tillage, seeds are directly planted into the soil, eliminating the need for a nursery of rice saplings. This not only saves time and labor but also reduces the cost of cultivation. Statement 3 is correct: Carbon sequestration refers to the process of capture and long-term storage of atmospheric carbon dioxide. In zero tillage, the carbon in the crop residue is returned to the soil, which helps in carbon sequestration. Therefore, all three statements are correct.