Every question from this NCERT chapter, with a detailed explanation.
Consider the following statements regarding the atmosphere: 1. It is a thin layer of air that surrounds the earth. 2. It extends only up to 10 km above the surface of the earth. 3. The air becomes denser as we move higher in the atmosphere. Which of the statements given above is/are correct?
With reference to the composition of air, consider the following statements: 1. Nitrogen and oxygen together make up approximately 99% of the air. 2. Carbon dioxide constitutes the majority of the remaining 1% of air. 3. The composition of air varies from place to place. Which of the statements given above is/are correct?
Consider the following statements regarding water vapour in the air: 1. Air contains water vapour only during the rainy season. 2. When air comes in contact with a cool surface, water vapour condenses. 3. The presence of water vapour in air is essential for the water cycle in nature. Which of the statements given above is/are correct?
With reference to the burning of fuel and its by-products, consider the following statements: 1. Burning can occur in the absence of oxygen if nitrogen is present. 2. Burning of fuel produces smoke which contains a few gases and fine dust particles. 3. Smoke produced by burning fuel is generally beneficial to respiratory health. Which of the statements given above is/are correct?
Consider the following statements regarding the "dust particles" in the air: 1. Dust particles are always present in the air. 2. The presence of dust particles in air is constant irrespective of time and place. 3. Breathing through the mouth can allow harmful dust particles to enter the body. Which of the statements given above is/are correct?
Which of the following pairs is correctly matched? | Component | Characteristic/Function 1. | Nitrogen | Supports burning 2. | Oxygen | Essential for respiration 3. | Smoke | Contains fine dust particles 4. | Hair in nose | Filters oxygen from air Select the correct answer using the code given below:
Consider the following statements regarding Carbon Dioxide (CO2) in the air: 1. It constitutes the largest component of the air around us. 2. It is produced by plants and animals during respiration. 3. Accumulation of CO2 in a closed room can cause suffocation. Which of the statements given above is/are correct?
With reference to the availability of oxygen to aquatic animals, consider the following statements: 1. Aquatic animals come to the surface to breathe air directly from the atmosphere. 2. Water contains air dissolved in it which is used by aquatic animals. 3. Heating water increases the amount of dissolved air in it. Which of the statements given above is/are correct?
Consider the following statements regarding air in the soil: 1. Dry soil contains air trapped between soil particles. 2. When water is poured on a lump of soil, it absorbs the water without displacing any air bubbles. 3. Organisms living in the soil require oxygen for respiration. Which of the statements given above is/are correct?
With reference to the balance of oxygen in the atmosphere, consider the following statements: 1. Plants produce carbon dioxide during photosynthesis. 2. Plants consume oxygen for respiration. 3. Plants produce more oxygen than they consume. Which of the statements given above is/are correct?
Consider the following statements regarding the interdependence of plants and animals: 1. Animals cannot live without plants due to the oxygen requirement. 2. The balance of oxygen is maintained solely by the respiration of animals. 3. Plants do not depend on animals for any gaseous exchange. Which of the statements given above is/are correct?
With reference to the structure of the atmosphere, how does air density vary with an increase in altitude?
With reference to the role of long chimneys in factories, consider the following statements: 1. They are used to bring fresh air into the factory. 2. They take harmful smoke and gases away from our noses. 3. They release the smoke and gases high up in the atmosphere. Which of the statements given above is/are correct?
The phenomenon where a beam of sunlight becomes visible in a dusty room is primarily attributed to which optical process?
Consider the following statements regarding the respiratory system and air: 1. We inhale air through our nostrils. 2. The fine hair and mucus in the nose are unable to filter out dust particles. 3. Breathing through the mouth is recommended to get more oxygen. Which of the statements given above is/are correct?
Match List I with List II and select the correct answer using the code given below: List I | List II A. Nitrogen | 1. Essential for water cycle B. Oxygen | 2. Major part of air, does not support burning C. Water Vapour | 3. Produced during burning, causes suffocation D. Carbon Dioxide | 4. Supports burning, essential for life
Consider the following statements about the "water cycle": 1. The water cycle is primarily driven by the heat of the sun. 2. The presence of water vapour in the air hinders the water cycle. 3. Air acts as a medium for the transport of water vapour. Which of the statements given above is/are correct?
With reference to the transmission of light through different media, clean atmospheric air is best classified as which of the following?
When water is heated, tiny bubbles appear on the inner surface of the container before the boiling point is reached. This phenomenon indicates:
Consider the following statements regarding the oxygen cycle: 1. Oxygen is consumed only by animals and not by plants. 2. Oxygen is returned to the atmosphere by plants. 3. Photosynthesis is the process by which plants produce oxygen. Which of the statements given above is/are correct?
With reference to the movement of air, consider the following statements: 1. Moving air is called wind. 2. Wind is generally too weak to uproot trees or blow off rooftops. 3. Windmills operate without the need for moving air. Which of the statements given above is/are correct?
Consider the following statements regarding the composition of smoke: 1. It contains a mixture of gases and fine dust particles. 2. It is composed entirely of water vapour. 3. It is produced by the burning of fuel. Which of the statements given above is/are correct?
Which of the following pairs is correctly matched regarding air components? Component | Percentage in Air (Approx) 1. Nitrogen and Oxygen | 99% 2. Carbon Dioxide | 21% 3. Other gases | 78% 4. Water Vapour | 50% Select the correct answer using the code given below:
Consider the following statements regarding the interdependence of plants and animals: 1. Plants consume carbon dioxide but do not produce oxygen. 2. Animals produce carbon dioxide which plants use. 3. This exchange highlights the interdependence of plants and animals. Which of the statements given above is/are correct?
Consider the following statements regarding the "oxygen" component of air: 1. It is necessary for the breakdown of food in organisms. 2. It is produced by burning fuels. 3. It is the most abundant gas in the atmosphere. Which of the statements given above is/are correct?
Which major constituent of the Earth's atmosphere plays a significant role in controlling combustion by acting as a diluent?
What is the primary cause of the respiratory distress experienced in a closed room containing burning material?
Considering the transmission of visible light through various substances, air is described as transparent because it:
With reference to the "respiration" in plants, consider the following statements: 1. Plants do not consume oxygen for respiration. 2. Plants produce carbon dioxide during respiration. 3. Respiration in plants occurs throughout the day and night. Which of the statements given above is/are correct?
Consider the following statements regarding the "photosynthesis" process: 1. Plants make their own food. 2. Carbon dioxide is the primary gas produced along with food. 3. Plants consume more oxygen in respiration than they produce in photosynthesis. Which of the statements given above is/are correct?
Which of the following acts as a primary abiotic agent for the dispersal of seeds in nature?
Consider the following statements regarding the "air in water": 1. It is essential for aquatic animals. 2. It cannot be removed even by boiling the water. 3. It is visible as bubbles when water is heated but not boiling. Which of the statements given above is/are correct?
Consider the following statements regarding the "atmosphere": 1. It is not essential for life on earth. 2. It protects us from harmful ultraviolet rays of the sun. 3. It is a mixture of gases. Which of the statements given above is/are correct?
What is the primary physiological reason for earthworms inhabiting the moist sub-surface soil?
Consider the following statements regarding "smoke": 1. It is produced by burning fuel. 2. It is beneficial for health. 3. It consists entirely of water vapour. Which of the statements given above is/are correct?
Which of the following is the most likely cause for transparent glass surfaces appearing hazy over time in an urban environment?
Consider the following statements regarding the "movement of air": 1. It helps in the rotation of firki. 2. It hinders the flying of kites. 3. It helps in the fluttering of book pages. Which of the statements given above is/are correct?
With reference to the "oxygen replacement" in the atmosphere, consider the following statements: 1. It is replaced solely by the respiration of animals. 2. It is replaced by the photosynthesis of plants. 3. It is a renewable resource maintained by nature. Which of the statements given above is/are correct?
Consider the following statements regarding "Nitrogen": 1. It is the most abundant gas in the air. 2. It supports burning. 3. It is toxic to all living organisms. Which of the statements given above is/are correct?
In an ecosystem, the interdependence between plants and animals is best exemplified by which of the following processes?
Consider the following statements regarding "aquatic animals": 1. They require oxygen for survival. 2. They cannot utilize the oxygen dissolved in water. 3. They produce carbon dioxide. Which of the statements given above is/are correct?
What is the primary physiological function of the fine hair and mucus lining the nasal cavity?
When an empty inverted bottle is tilted while submerged in water, air bubbles escape and water enters. This phenomenon demonstrates that:
Consider the following statements regarding "wind": 1. It refers to the static layer of air near the ground. 2. It helps in the water cycle. 3. It aids in the dispersal of seeds and pollen. Which of the statements given above is/are correct?
Consider the following statements regarding the "composition of air": 1. It contains nitrogen, oxygen, carbon dioxide, water vapour, and dust. 2. The amount of dust is constant everywhere. 3. The presence of water vapour is irrelevant to the water cycle. Which of the statements given above is/are correct?
From a chemical perspective, atmospheric air is classified as a mixture rather than a compound because:
Consider the following statements regarding "respiration" in soil organisms: 1. They use air trapped in soil. 2. Heavy rains increase the availability of air in the soil. 3. They depend on oxygen for respiration. Which of the statements given above is/are correct?
Which of the following is a correct statement about "Carbon Dioxide"? 1. It is consumed during the process of burning. 2. It is produced during respiration. 3. It is a component of the air we exhale. Select the correct answer using the code given below:
Consider the following statements regarding the "uses of air": 1. It helps birds and bats to fly. 2. It creates a vacuum that prevents aeroplanes from flying. 3. It is not effective for separating sand and sawdust. Which of the statements given above is/are correct?
Consider the following statements regarding the presence of air: 1. Air is present in an "empty" open bottle. 2. Water is completely devoid of any dissolved air. 3. Air is present in soil. Which of the statements given above is/are correct?
What is the primary ecological reason that soil-dwelling organisms, such as earthworms, surface during heavy rainfall?