Multiple Choice Questions 1. Which of the following is not a physical change? (a) Boiling of water to give water vapour (b) Melting of ice to give water (c) Dissolution of salt in water (d) Combustion of Liquefied Petroleum Gas (LPG) Soln: Answer is (d) Combustion of Liquefied Petroleum Gas (LPG) Explanation: Combustion is always …
Chemical Equations and Reactions, Chapter-1, Class 10, CBSE, NCERT Exemplar Read More »
Multiple Choice Questions 1. Which of the following property is generally not shown by metals? (a) Electrical conduction (b) Sonorous in nature (c) Dullness (d) Ductility Soln: Answer is (c) Dullness 2. The ability of metals to be drawn into thin wires is known as (a) ductility (b) malleability (c) sonorousity (d) conductivity Soln: …
Metal and Non-Metal, Chapter-3, Class 10, CBSE, NCERT Exemplar Read More »
Environmental Issues, Class 12, Biology, CBSE 2 Environmental Issues Causes of air pollution The main causes of air pollution are as follows:(a) Exhaust from Automobiles: Most of the automobiles use fossil fuels. Burning of fossil fuel releases carbon dioxide and carbon monoxide. Carbon dioxide is a greenhouse gas. Carbon monoxide is a poisonous gas even …
Transportation of Oxygen in Human beings
Class 10, Life Process, Chapter 6, Respiratory System
1 Theories of Origin of Life and EvolutionTheories of Origin of Life(i) In previous days, people believed that the universe and life on it was an act and result of God’s creation.(ii) There was, however, no evidence to support these claims.(iii) The early scientists and Greeks believed that life on Earth never began on Earth …
– All formulas of the chapter at one glance. 1 Hardy-Weinberg Equilibrium Hardy-Weinberg principle states that the genetic constitution in a population remains constant if there is no external influence. This statement gives us a formula that is used to solve the numerical problems of this chapter. Check the formula and the example below. 2 Calculating …
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