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Coal is the most important and abundant fossil fuel in India.’ Justify the statement by evaluating the significant role it plays in the growth of the Indian economy in its different forms.
Coal plays a crucial role in India’s economic and industrial growth. Energy source: Nearly 70% of India’s electricity is generated from coal-based thermal power plants. Industrial use: Coal is essential in steel, cement, and chemical industries as a raw material and energy source. Employment and revRead more
Coal plays a crucial role in India’s economic and industrial growth.
Being the most abundant fossil fuel in India, coal ensures energy security and supports economic expansion, though its environmental impact highlights the need for sustainable and cleaner energy alternatives.
See lessWhat is essential for resource development to contribute to overall development?
Resource availability alone cannot ensure progress. Technological development enables scientific use and value addition of natural resources, while institutional changes like proper policies, training, and management systems help in equitable and efficient utilization. Together, they ensure that resRead more
Resource availability alone cannot ensure progress. Technological development enables scientific use and value addition of natural resources, while institutional changes like proper policies, training, and management systems help in equitable and efficient utilization. Together, they ensure that resource development leads to sustainable economic growth, environmental balance, and improvement in the quality of life for all.
See lessFour statements about the reactions of oxides with dilute hydrochloric acid and aqueous sodium hydroxide are listed. I. Aluminium oxide reacts with both dilute hydrochloric acid and aqueous sodium hydroxide. II. Calcium oxide reacts with dilute hydrochloric acid and aqueous sodium hydroxide. III. Zinc oxide reacts with both dilute hydrochloric acid and aqueous sodium hydroxide. IV. Sulphur dioxide does not react with either dilute hydrochloric acid or aqueous sodium hydroxide. Which statements are correct?
Answer: Aluminium oxide and zinc oxide are amphoteric oxides; they react with dilute hydrochloric acid to form corresponding chlorides and with aqueous sodium hydroxide to form soluble aluminates or zincates. Calcium oxide is a basic oxide; it reacts with dilute hydrochloric acid but not with sodiumRead more
Answer: Aluminium oxide and zinc oxide are amphoteric oxides; they react with dilute hydrochloric acid to form corresponding chlorides and with aqueous sodium hydroxide to form soluble aluminates or zincates. Calcium oxide is a basic oxide; it reacts with dilute hydrochloric acid but not with sodium hydroxide. Sulphur dioxide is an acidic oxide; it does not react with hydrochloric acid but reacts with bases like sodium hydroxide to give sulphites/bisulphites, so statement IV is incorrect here.
See lessAn iron nail is added to each of the two test tubes ‘P’ and ‘Q’ containing aqueous copper (II) sulphate, and aqueous silver nitrate respectively. Which of the following observation is correct?
Answer: When an iron nail is placed in aqueous copper(II) sulphate (tube P), iron, being more reactive, displaces copper ions; copper is deposited as reddish-brown metal on the nail and iron goes into solution as Fe²⁺. In aqueous silver nitrate (tube Q), iron similarly displaces silver; silver metalRead more
Answer: When an iron nail is placed in aqueous copper(II) sulphate (tube P), iron, being more reactive, displaces copper ions; copper is deposited as reddish-brown metal on the nail and iron goes into solution as Fe²⁺. In aqueous silver nitrate (tube Q), iron similarly displaces silver; silver metal plates the nail producing a silver coating while iron salts form in the solution. Thus both tubes show displacement reactions, with copper and silver metals deposited respectively during the experiment period.
See lessWhich of the following substances when dissolved in equal volume of water, will have the highest pH value?
Sodium hydroxide will give the highest pH when equal volumes are dissolved because it is a strong base that dissociates completely to yield a high concentration of hydroxide ions. Magnesium hydroxide, although a base, is sparingly soluble so it produces far fewer OH⁻ ions in solution. Sulphuric acidRead more
Sodium hydroxide will give the highest pH when equal volumes are dissolved because it is a strong base that dissociates completely to yield a high concentration of hydroxide ions. Magnesium hydroxide, although a base, is sparingly soluble so it produces far fewer OH⁻ ions in solution. Sulphuric acid is a strong acid and acetic acid is a weak acid; both produce H⁺ ions and lower pH values, so their solutions will be much less alkaline than NaOH commonly. Correct option – D.
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