Is Matter Around Us Pure (क्या हमारे आस-पास के पदार्थ शुद्ध है) Ch(2) Practice Quiz in Hindi Part – 1 || Class 9 Science Practice Quizzes in English Posted on February 28, 2025February 28, 2025 by Anshul Gupta0% 0 votes, 0 avg 3 Is Matter Around Us Pure (क्या हमारे आस-पास के पदार्थ शुद्ध है) Ch(2)Practice Quiz in Hindi Part – 1 || Class 9 Science Practice Quizzes in English 1 / 201. What is the concentration of a solution containing 20 g of salt dissolved in 180 g of water? A. 10% B. 40% C. 30% D. 20% Explanation: The concentration of a solution can be calculated using the formula: (mass of solute / mass of solution) x 100. In this case, the mass of the solute (salt) is 20 g, and the mass of the solution is 200 g (20 g salt + 180 g water). So, the concentration is (20 g / 200 g) x 100 = 10%. 2 / 202. Which of the following is an example of a chemical change? A. Melting of ice B. Burning of wood C. Boiling of water D. Dissolving sugar in water Explanation: Burning wood involves a chemical reaction between the wood and oxygen, producing new substances like ash, carbon dioxide, and water vapor. 3 / 203. What is the size range of particles in a colloid? A. 1 nm to 1000 nm B. Greater than 1000 nm C. Any size D. Less than 1 nm Explanation: Colloidal particles are larger than molecules but not large enough to be seen with the naked eye. They range from 1 to 1000 nanometers in diameter. 4 / 204. What is the dispersed phase in a colloidal solution? A. The component in which the dispersed phase is suspended B. The component present in larger amount C. The component present in lesser amount D. The solute-like component or the dispersed particles Explanation: In a colloid, the dispersed phase is the substance that is distributed throughout the dispersion medium. It is analogous to the solute in a solution. 5 / 205. Which of the following is an example of a heterogeneous mixture? A. Sand and water B. Saltwater C. Air D. Lemonade Explanation: A heterogeneous mixture has a non-uniform composition, meaning the components are not evenly distributed. In sand and water, the sand particles are clearly distinguishable from the water. 6 / 206. What is a saturated solution? A. A solution that can dissolve more solute at a given temperature B. A solution that is cooled to a low temperature C. A solution that cannot dissolve any more solute at a given temperature D. A solution that is heated to a high temperature Explanation: A saturated solution is a solution in which the maximum amount of solute has been dissolved at a given temperature. 7 / 207. What is the difference between a compound and a mixture? A. A compound can be separated by physical methods, while a mixture cannot. B. A compound is formed by a chemical change, while a mixture is formed by a physical change. C. A compound shows the properties of its constituent substances, while a mixture does not. D. A compound has a fixed composition, while a mixture has a variable composition. Explanation: A compound is formed when two or more elements chemically combine in a fixed ratio. A mixture is formed when two or more substances are combined physically, and their ratio can vary. 8 / 208. What is the Tyndall effect? A. The separation of a mixture by filtration B. The scattering of light by particles in a colloid C. The settling of particles in a suspension D. The dissolving of a solute in a solvent Explanation: The Tyndall effect is the scattering of light as a light beam passes through a colloid. The individual suspension particles scatter and reflect light, making the beam visible. 9 / 209. Which of the following is NOT a property of a solution? A. Solute particles cannot be separated by filtration B. Homogeneous mixture C. Stable D. Path of light is visible Explanation: The particles in a solution are too small to scatter light, so the path of light is not visible. 10 / 2010. Which of the following is NOT a pure substance? A. Compound B. Mixture C. Element D. All of the above Explanation: A pure substance consists of only one type of particle, either an element or a compound. A mixture contains more than one substance mixed in any proportion. 11 / 2011. Which of the following is NOT a property of a suspension? A. Particles are visible to the naked eye B. Stable C. Heterogeneous mixture D. Particles scatter light Explanation: Suspensions are unstable, meaning the particles will settle down over time due to gravity. 12 / 2012. Which of the following is an example of a physical change? A. Cooking of food B. Rusting of iron C. Burning of a candle D. Melting of butter Explanation: Melting butter is a physical change because it only changes the state of the substance from solid to liquid, without altering its chemical composition. 13 / 2013. What is the dispersion medium in a colloid? A. The component in which the dispersed phase is suspended B. The solute-like component or the dispersed particles C. The component present in larger amount D. The component present in lesser amount Explanation: The dispersion medium is the substance in which the dispersed phase is distributed. It is analogous to the solvent in a solution. 14 / 2014. Which of the following is an example of a colloid? A. Sand and iron filings B. Milk C. Saltwater D. Sugar dissolved in water Explanation: Milk is a colloid because it contains tiny droplets of fat dispersed throughout the water, and these droplets scatter light, exhibiting the Tyndall effect. 15 / 2015. What is an alloy? A. A suspension B. A solid solution of two or more metals or a metal and a non-metal C. A compound D. A pure substance Explanation: An alloy is a mixture of two or more metals, or a metal and a non-metal, that cannot be separated into their components by physical methods. 16 / 2016. Which of the following is an example of a compound? A. Air B. Oxygen C. Iron D. Carbon dioxide Explanation: Carbon dioxide is a compound because it is composed of two elements, carbon and oxygen, chemically combined in a fixed proportion. 17 / 2017. What is the difference between a solution and a suspension? A. All of the above B. The particles in a solution do not settle down, while those in a suspension do. C. The particles in a solution are smaller than those in a suspension. D. A solution is homogeneous, while a suspension is heterogeneous. Explanation: Solutions and suspensions differ in their homogeneity, particle size, and stability. Solutions are homogeneous, have tiny particles, and are stable, while suspensions are heterogeneous, have larger particles, and are unstable. 18 / 2018. Which of the following is NOT a characteristic property of metals? A. Lustre B. Malleable C. Ductile D. Poor conductor of heat and electricity Explanation: Metals are good conductors of heat and electricity. 19 / 2019. Which of the following is an example of an element? A. Sugar B. Salt C. Water D. Gold Explanation: Gold is an element because it cannot be broken down into simpler substances by chemical reactions. 20 / 2020. Which of the following is NOT a method of expressing the concentration of a solution? A. Temperature by temperature percentage B. Mass by volume percentage C. Mass by mass percentage D. Volume by volume percentage Explanation: The concentration of a solution is typically expressed as the amount of solute relative to the amount of solvent or solution. The methods mentioned in the text are mass by mass percentage, mass by volume percentage, and volume by volume percentage. Please insert your information to see your ranking अपनी Ranking जानने के लिए कृपया अपनी जानकारी भरे NamePhone Number Your score isThe average score is 37% 0% Restart quiz Category: Class 9 Science Quizzes in English