Fusion is a phenomenon in which a Liquid changes into solid b Gas changes into solid c liquid changes into gas d Solid changes into liquid Answer: Solid changes into liquid 4. Kinetic energy is the energy possessed by a particle due to its motion. Convert the following temperatures to Celsius scale. For other answers visit to or and in English or go for Solutions. Shape defines a definite boundary.
Liquid evaporation happens at a Temperature lower than boiling point b constant temperature c at boiling point d All temperatures Answer : Temperature lower than boiling point 2. Therefore, burns produced by steam are more severe than those produced by boiling water. Why is ice at 273 K more effective in cooling than water at the same temperature? Therefore, this heat does not contribute in increasing the temperature of the substance. Name A, B, C, D, E and F in the following diagram showing change in its state. Video Solution Answer: Sugar is a solid; the forces of attraction between the particles of sugar are strong. What is the usage of high compressibility property of gas? Answer: Latent heat of fusion is the amount of heat energy needs to transform 1 kilogram of solid into liquid at its melting point is known as latent heat of fusion. Question 3: Why is respiration considered an exothermic reaction? On the other hand, wood has little space between its particles.
Matter can exist in three physical states—solid, liquid, and gaseous. For this reason, we are able to sip hot tea or milk faster from a saucer than a cup. Answer 1 Any substance that occupies space and having mass is called matter. The major groups of activities for improving crop yields — Crop variety improvement, Crop production improvement, Crop protection management. The intermolecular spaces in liquids is fair enough to let the diver pass through it. These spaces are larger as compared to the spaces present between the particles of water. The temperature increases and the ice melts from solid to form a liquid.
Hence as we know earlier, the heavier substance sinks while the lighter one floats above. Video Solution Answer: a The differences in the characteristics of states of matter are given in the following table. Visit to main page or move to of the page. Plasmas have an indefinite shape and an indefinite volume because the particles can move past one another. On the other hand, cotton is a good absorber of water.
This is how the French Revolution came about. Answer a Naphthalene balls disappear with time without leaving any solid because of they undergoes sublimation easily i. For example: Question 2: Explain the following terms with examples in each case: i Oxidation and ii Reduction. This is because all the heat supplied to increase the temperature is utilised in changing the state by overcoming the forces of attraction between the particles. Also the water has tiny, weak hydrogen bonds which, in their billions, hold water molecules together for small fractions of a second.
During evaporation, particles of the liquid absorb energy from the surrounding or the surface of the palm to compensate for the loss of energy, making the surroundings cool. All these topics are explained with the help of practical activities and solved numerical problems given within the textbook as examples. The Directors often clashed with the legislative councils, who then made attempts to dismiss them. Answer: Steam has more energy than boiling water. This is due to an increase in the kinetic energy of solid particles.
Hence it would be present in both liquid and gaseous state. Hence, at 273 K, ice is more effective in cooling than water. The number of particle per unit volume is completely small. Which property of matter does this observation show? Therefore, we can get the smell of perfume sitting several metres away. Topic such as Inertia and Mass and Second Law of Motion including mathematical formulation of second law of motion have been described with the help of numerical based problems and diagrams.
This leads to absorption of energy from the surroundings, thereby cooling the surroundings. Concepts on uniform circular motion. Answer : A quantity representing the amount of water vapour in the atmosphere or in a gas. Answer A desert cooler increases the humidity of the surrounding air. Give reasons for the following observation: The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close.
All these topics are explained with the help of practical activities and solved numerical problems given within the textbook as examples. Convert the following temperatures to Celsius scale. Page No 24: Answer: The message of universal rights was beset with contradictions. Why are we able to sip hot tea or milk faster from a saucer than a cup? The air around us cannot hold more than a definite amount of water vapour at a given temperature. The intermolecular spaces in liquids is fair enough to let the diver pass through it. Therefore, this heat does not contribute in increasing the temperature of the substance.