(c) Low temperature, high pressure Gases can be liquefied by lowering the temperature and increasing the pressure. Low temperature slows down gas molecules, reducing their kinetic energy, while high pressure forces the molecules closer together, allowing them to form a liquid state. https://www.tiwaRead more
(c) Low temperature, high pressure
Gases can be liquefied by lowering the temperature and increasing the pressure. Low temperature slows down gas molecules, reducing their kinetic energy, while high pressure forces the molecules closer together, allowing them to form a liquid state.
(c) On increasing pressure and on adding more hydrogen gas to the cylinder (increasing the pressure), the molecules will come closer. Therefore, observations in (i) and (iv) are wrong. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
(c) On increasing pressure and on adding more hydrogen gas to the cylinder (increasing the pressure), the molecules will come closer. Therefore, observations in (i) and (iv) are wrong.
The correct answer is: (a) Vinegar solution. A true solution is a homogeneous mixture where solute particles are completely dissolved in the solvent and cannot be seen under a microscope. Vinegar is a true solution of acetic acid in water, making it a homogeneous mixture. https://www.tiwariacademy.cRead more
The correct answer is: (a) Vinegar solution. A true solution is a homogeneous mixture where solute particles are completely dissolved in the solvent and cannot be seen under a microscope. Vinegar is a true solution of acetic acid in water, making it a homogeneous mixture.
The correct answer is: (b) NaCl. Common salt, also known as table salt, is primarily composed of sodium chloride (NaCl). It is an ionic compound made of sodium (Na⁺) and chloride (Cl⁻) ions, essential for human health and widely used in food and industry. https://www.tiwariacademy.com/ncert-solutionRead more
The correct answer is: (b) NaCl. Common salt, also known as table salt, is primarily composed of sodium chloride (NaCl). It is an ionic compound made of sodium (Na⁺) and chloride (Cl⁻) ions, essential for human health and widely used in food and industry.
The correct answer is: (b) (i) and (iii). Pure substances contain only one kind of particles, either atoms or molecules. Pure substances have a uniform composition throughout. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
The correct answer is: (b) (i) and (iii).
Pure substances contain only one kind of particles, either atoms or molecules.
Pure substances have a uniform composition throughout.
The correct answer is: (c) (i), (iii), and (iv) (i) Incorrect – The product A₂B is a new substance with different properties from A and B. (ii) Correct – Compounds always have a fixed composition. (iii) Incorrect – A₂B is a compound because it is formed by the chemical combination of A and B. (iv) IRead more
The correct answer is: (c) (i), (iii), and (iv)
(i) Incorrect – The product A₂B is a new substance with different properties from A and B.
(ii) Correct – Compounds always have a fixed composition.
(iii) Incorrect – A₂B is a compound because it is formed by the chemical combination of A and B.
(iv) Incorrect – A compound is different from an element; A₂B is not an element.
(c) Oxygen, water, sugar In matter, the force of attraction between particles increases from gases to liquids to solids. Oxygen (gas) has the weakest forces, water (liquid) has moderate forces, and sugar (solid) has the strongest intermolecular forces. https://www.tiwariacademy.com/ncert-solutions/cRead more
(c) Oxygen, water, sugar
In matter, the force of attraction between particles increases from gases to liquids to solids. Oxygen (gas) has the weakest forces, water (liquid) has moderate forces, and sugar (solid) has the strongest intermolecular forces.
(c) 308 K, 329 K, 391 K. To convert Celsius to Kelvin: K = °C + 273 Diethyl ether: 35°C + 273 = 308 K Acetone: 56°C + 273 = 329 K n-Butyl alcohol: 118°C + 273 = 391 K https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
(c) 308 K, 329 K, 391 K.
To convert Celsius to Kelvin:
K = °C + 273
Diethyl ether: 35°C + 273 = 308 K
Acetone: 56°C + 273 = 329 K
n-Butyl alcohol: 118°C + 273 = 391 K
The correct answer is: (c) Corrosion and it is a chemical change. Rusting occurs when iron reacts with oxygen and moisture, forming iron oxide (rust). This process alters the chemical composition of iron, making it a chemical change rather than a physical one. https://www.tiwariacademy.com/ncert-solRead more
The correct answer is: (c) Corrosion and it is a chemical change. Rusting occurs when iron reacts with oxygen and moisture, forming iron oxide (rust). This process alters the chemical composition of iron, making it a chemical change rather than a physical one.
(b) Germanium, because it has both type of characteristics like metal and non-metal. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
(b) Germanium, because it has both type of characteristics like metal and non-metal.
Seema visited a Natural Gas Compressing Unit and found that the gas can be liquefied under specific conditions of temperature and pressure. While sharing her experience with friends she got confused. Help her to identify the correct set of conditions. (a) Low temperature, low pressure (b) High temperature, low pressure (c) Low temperature, high pressure (d) High temperature, high pressure
(c) Low temperature, high pressure Gases can be liquefied by lowering the temperature and increasing the pressure. Low temperature slows down gas molecules, reducing their kinetic energy, while high pressure forces the molecules closer together, allowing them to form a liquid state. https://www.tiwaRead more
(c) Low temperature, high pressure
Gases can be liquefied by lowering the temperature and increasing the pressure. Low temperature slows down gas molecules, reducing their kinetic energy, while high pressure forces the molecules closer together, allowing them to form a liquid state.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
See lessIn which of the following conditions, the distance between the molecules of hydrogen gas would increase? (i) Increasing pressure on hydrogen contained in a closed container. (ii) Some hydrogen gas leaking out of the container. (iii) Increasing the volume of the container of hydrogen gas. (iv) Adding more hydrogen gas to the container without increasing the volume of the container. (a) (i) and (iii) (b) (i) and (iv) (c) (ii) and (iii) (d) (ii) and (iv)
(c) On increasing pressure and on adding more hydrogen gas to the cylinder (increasing the pressure), the molecules will come closer. Therefore, observations in (i) and (iv) are wrong. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
(c) On increasing pressure and on adding more hydrogen gas to the cylinder (increasing the pressure), the molecules will come closer. Therefore, observations in (i) and (iv) are wrong.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
See lessWhich of the following is a true solution? (a) Vinegar solution (b) Blood (c) Milk (d) Muddy water
The correct answer is: (a) Vinegar solution. A true solution is a homogeneous mixture where solute particles are completely dissolved in the solvent and cannot be seen under a microscope. Vinegar is a true solution of acetic acid in water, making it a homogeneous mixture. https://www.tiwariacademy.cRead more
The correct answer is: (a) Vinegar solution. A true solution is a homogeneous mixture where solute particles are completely dissolved in the solvent and cannot be seen under a microscope. Vinegar is a true solution of acetic acid in water, making it a homogeneous mixture.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
See lessWhat is the major compound present in common salt? (a) MgCl₂ (b) NaCl (c) CaCl2 (d) KCl
The correct answer is: (b) NaCl. Common salt, also known as table salt, is primarily composed of sodium chloride (NaCl). It is an ionic compound made of sodium (Na⁺) and chloride (Cl⁻) ions, essential for human health and widely used in food and industry. https://www.tiwariacademy.com/ncert-solutionRead more
The correct answer is: (b) NaCl. Common salt, also known as table salt, is primarily composed of sodium chloride (NaCl). It is an ionic compound made of sodium (Na⁺) and chloride (Cl⁻) ions, essential for human health and widely used in food and industry.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
See lessWhich of the following statements are correct for pure substances? (i) Pure substances contain only one kind of particles. (ii) Pure substances may be compounds or mixtures. (iii) Pure substances have the same composition throughout. (iv) Pure substances can be exemplified by all elements other than copper. (a) (i) and (ii) (b) (i) and (iii) (c) (iii) and (iv) (d) (ii) and (iii)
The correct answer is: (b) (i) and (iii). Pure substances contain only one kind of particles, either atoms or molecules. Pure substances have a uniform composition throughout. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
The correct answer is: (b) (i) and (iii).
Pure substances contain only one kind of particles, either atoms or molecules.
Pure substances have a uniform composition throughout.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
See lessTwo substances A and B were made to react to form a third substance A₂B according to the following reaction: 2A + B → A₂B Which of the following statements concerning this reaction are incorrect? (i) The product A₂B shows the properties of the substances A and B. (ii) The product will always have a fixed composition. (iii) The product so formed cannot be classified as a compound. (iv) The product so formed is an element. (a) (i), (ii) and (iii) (b) (i), (ii) and (iv) (c) (i), (iii) and (iv) (d) (ii), (iii) and (iv)
The correct answer is: (c) (i), (iii), and (iv) (i) Incorrect – The product A₂B is a new substance with different properties from A and B. (ii) Correct – Compounds always have a fixed composition. (iii) Incorrect – A₂B is a compound because it is formed by the chemical combination of A and B. (iv) IRead more
The correct answer is: (c) (i), (iii), and (iv)
(i) Incorrect – The product A₂B is a new substance with different properties from A and B.
(ii) Correct – Compounds always have a fixed composition.
(iii) Incorrect – A₂B is a compound because it is formed by the chemical combination of A and B.
(iv) Incorrect – A compound is different from an element; A₂B is not an element.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
See lessA few substances are arranged in the increasing order of forces of attraction between their particles. Which one of the following represents a correct arrangement ? (a) Water, air, wind (b) Air, sugar, oil (c) Oxygen, water, sugar (d) Salt, juice, air
(c) Oxygen, water, sugar In matter, the force of attraction between particles increases from gases to liquids to solids. Oxygen (gas) has the weakest forces, water (liquid) has moderate forces, and sugar (solid) has the strongest intermolecular forces. https://www.tiwariacademy.com/ncert-solutions/cRead more
(c) Oxygen, water, sugar
In matter, the force of attraction between particles increases from gases to liquids to solids. Oxygen (gas) has the weakest forces, water (liquid) has moderate forces, and sugar (solid) has the strongest intermolecular forces.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
See lessThe boiling points of diethyl ether, acetone and n-butyl alcohol are 35 °C, 56 °C and 118 °C respectively. Which one of the following correctly represents their boiling points in kelvin scale? (a) 306 K, 329 K, 391 K (b) 308 K, 329 K, 392 K (c) 308 K, 329 Κ, 391 Κ (d) 329 K, 392 Κ, 308 K
(c) 308 K, 329 K, 391 K. To convert Celsius to Kelvin: K = °C + 273 Diethyl ether: 35°C + 273 = 308 K Acetone: 56°C + 273 = 329 K n-Butyl alcohol: 118°C + 273 = 391 K https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
(c) 308 K, 329 K, 391 K.
To convert Celsius to Kelvin:
K = °C + 273
Diethyl ether: 35°C + 273 = 308 K
Acetone: 56°C + 273 = 329 K
n-Butyl alcohol: 118°C + 273 = 391 K
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-1/
See lessRusting of an article made up of iron is called (a) corrosion and it is a physical as well as chemical change. (b) dissolution and it is a physical change. (c) corrosion and it is a chemical change. (d) dissolution and it is a chemical change.
The correct answer is: (c) Corrosion and it is a chemical change. Rusting occurs when iron reacts with oxygen and moisture, forming iron oxide (rust). This process alters the chemical composition of iron, making it a chemical change rather than a physical one. https://www.tiwariacademy.com/ncert-solRead more
The correct answer is: (c) Corrosion and it is a chemical change. Rusting occurs when iron reacts with oxygen and moisture, forming iron oxide (rust). This process alters the chemical composition of iron, making it a chemical change rather than a physical one.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
See lessOut of these, which one is metalloid?
(b) Germanium, because it has both type of characteristics like metal and non-metal. https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
(b) Germanium, because it has both type of characteristics like metal and non-metal.
https://www.tiwariacademy.com/ncert-solutions/class-9/science/chapter-2/
See less