MATTER IN OUR SURROUNDINGS 9

Practice paper

Subject Chemistry (2020)

CH-1 MATTER IN OUR SURROUNDINGS

Class IX 

               

I. Very short answer type questions:

1. Define latent heat.  
2. Define sublimation.
3. A sponge is a solid, yet we are able to compress it. Why? 
4. Convert 373 C to the Kelvin.
5. Latent heat of evaporation of two liquids A and B is 100 J/kg and 150 J/kg respectively. Which one can produce a more cooling effect and why?
6. What happens to the melting point of solid with an increase in pressure? 
7. Name the state of matter that has minimum space between particles. 
8. Name the property of gas that helps aquatic plants and animals to survive in water?
9. How can we liquefy gases?
10. Which of the following is matter? Chair, air, love, smell, hate, almonds, thought, cold, cold drink, the smell of perfume.            
11. The mass per unit volume of a substance is called density. (Density = mass/volume). Arrange the following in order of increasing density –      Air, exhaust from chimneys, honey, water, chalk, cotton, and iron.
12. Are the three states of matter inter-convertible? How can they interconnect? 
13. Define matter.
14. Write the full form of LPG and CNG
15. Write the two factors that determine the rate of diffusion.
16. What is the SI unit of volume? 
17. 1L = _____ mL, 1 mL = ________cm3.
18. Define fusion.
19. What is the unit of measuring the pressure exerted by a gas?
20. Define atmospheric pressure.
21. What is the atmospheric pressure at sea level?
22. What does the melting point of a solid indicate? 
23. What is frosting?
24. Write an expression for the relation between Celsius C and Fahrenheit F.
25. 1 atmosphere = _____________ Pa.

II. Short answer type questions:

1. Explain why heat energy is needed to melt a solid?
2. Explain the state of matter on the basis of kinetic theory.
3. Write the S.I units of the followings:(i) Mass (ii) Length  ( iii) Temperature  (iv)Force  (v) Volume  (vi)Density  (vii)Pressure.
4. Give reasons for the following observation: The smell of hot sizzling food reaches you several meters away, but to get the smell from cold food you have to go close. 
5. A diver is able to cut through water in a swimming pool. Which property of 
6. What are the characteristics of the particles of matter?
7. State the form of energy possessed by particles of matter in motion? How does the increase in temperature affect the rate of diffusion?  
8. Define the kinetic theory of matter. 
9. Define the latent heat of vaporization and latent heat of fusion.
10. Why should we wear cotton clothes in summer?
11. Write the two differences between gas and vapour? 
12. What happens when the temperature of the solids increase?
13. When heat is being supplied to a solid, then what does the heat energy due to the particles of solid?
14. Why is it that on increasing the wind speed the rate of evaporation increases?
15. Why do we say that evaporation is a surface phenomenon?
16. Why is it that a wooden chair should be called a solid and not a liquid?
17. How does evaporation cause cooling?
18. Why does our Palm feel cold when we put some acetone or petrol or petroleum on it?
19. Why does the water kept in an earthen pot becomes cool during summer?
20. Why does a desert cooler cool better on a hot dry day?
21. Explain the interconversion of three states of matter with the help of a chart or diagram. Name the process of each conversion. 
22. Discuss the various factors affect the rate of evaporation. 
23. How does pressure help in liquefaction of gas? Name two liquefied gases used in daily life.
24. Gases are more compressible, write two reasons for this.
25. If the boiling points of oxygen-argon and nitrogen are -182, -186 and -196c 
    (a) Which gas forms the liquid first as the air is cooled? 
    (b) Which gas is obtained first when liquid air boils up?
26. Why do we see water droplets on the outer the surface of a glass containing ice-cold water?
27. During the summer, we perspire more. Why?
28. When we dissolve salt in water, the level of water does not change. Why?
29. The melting point of sodium and potassium are 370K and 336K. What information it can provide?
30. Water boils below 100 degrees C at the mountain. Explain.
31. The heat energy is more in steam than in water at 100 degrees C or 373 K (100C + 273). Why?
32. The heat energy is more in the water at 0 degrees C or 273 as compared to particles in ice at the same temperature. Why? 
33. Convert the following temperatures to the Kelvin scale:
34. (a) 35 degree C  (b) 273 degree C 
35. Convert the following temperatures to the Celsius scale:
36. (a) 400 k  (b) 673 k.
37. Give two reasons for saying that coal is solid.

III. Long answer type questions:

1. Comment upon the following: rigidity, compressibility, fluidity, filling a gas container, shape, kinetic energy, and density.
2. Tabulate the differences in the characteristics of states of matter. Or explain how the states of matter arise due to variation in the characteristics of the particle.
3. Give reasons:
   (a) A gas fills completely the vessel in which it is kept.
   (b) A gas exerts pressure on the walls of the container
   (c) A wooden table should be called a solid.
   (d) We can easily move our hand in the air but to do the same through a solid block of wood we need a karate expert.
4. Give reasons for the following taking into evaporation:
   (a) While putting clothes for drying up we spread them out.
   (b) Clothes dry up faster when spread near a heater. 
   (c) Clothes take a very long time to dry on a rainy day.
5. Carbon dioxide was taken in an enclosed cylinder and compressed by applying pressure.
   (a) Which state of matter will be obtained after completion of the process? 
   (b) Name and define this process.
   (c) What is the common name of the product obtained in the above process?
6. What is the effect of a change of pressure on the physical state of matter?    Explain with an example of a gas.
7. What is the effect of an increase in temperature on the solid-state of matter? Explain. 
8. Name two processes that illustrate that on heating, movement of particles of matter increases. Define fluidity. Explain why liquids flow.
9. (i) Convert the following temperature to Celsius scale:
   (a) 300 K   (b) 573 K.
   (ii) What is the physical state of water at:
   (a) 250ºC  (b) 100ºC ?
   (iii) For any substance, why does the temperature remain constant during the change of state?
   (iv) Suggest a method to liquefy atmospheric gases.
10. Give reason after a hot sunny day people sprinkle water on the roof or open ground.
11. State the reasons for the following:
    (a)The smell of lighted incense stick reaches you several meters away, but to get the smell from an unlighted incense stick you have to go close.
    (b) The naphthalene balls disappear with time without leaving any solid.
12. The rate of diffusion is faster in gas. Why?
13. Why gases exert pressure on the walls of containers?
14. Write any three differences between evaporation and boiling.
15. The temperature-time graph given below shows the heating curve for pure wax. After studying the graph answer the following questions:
    (a) What is the physical state of a substance at points A, B, C, and D?
    (b) What is the melting point of the substance?
    (c) What is its boiling point?
    (d) Which portions of the graph indicate that change of state is taking place? Name the term used for heat absorbed during changing the state involved in the above process.  
16. How can we obtain different gases from the air? Draw the flow diagram to show the state of the process. 
17. What are the characteristics of Particles of Matter?
    (a) Can a rubber band it change its shape on stretching? Is it solid? 
    (b) When sugar and salts are kept in different jars these take the shape of the jar. Are they solid?
18. The rate of diffusion of liquids is higher than that of solids. Why?
19. What happens to the particles of matter during the change of states?
20. Explain about the Bose-Einstein Condensate and plasma state of matter.
21. Why the interconversion of the state of matter is considered as a physical change? Give three reasons to justify your answer.
22. Give reasons to justify:
    (a) Gases diffuse but not solids.
    (b) We see water droplets on the outer surface of a glass containing cold water.
    (c) We are able to sip hot tea or milk faster from a saucer rather than a cup.
23. Give two differences between (a) solid and liquid (b) liquid and gas.
24. Write an activity to show the process of evaporation.

NCERT QUESTIONS:

1. Which of the following are matter? Chair, air, love, smell, hate, almonds, thought, cold, cold drink, the smell of perfume. 
2. Give reasons for the following observation: The smell of hot sizzling food reaches you several meters away, but to get the smell from cold food you have to go close. 
3. A diver is able to cut through water in a swimming pool. Which property of matter does this observation show? 
4. What are the characteristics of the particles of matter?
5. The mass per unit volume of a substance is called density. (density = mass/volume). Arrange the following in order of increasing density – air, exhaust from chimneys, honey, water, chalk, cotton, and iron. 
6. (a) Tabulate the differences in the characteristics of states of matter.
   (b) Comment upon the following: rigidity, compressibility, fluidity, filling a gas container, shape, kinetic energy, and density.
7.  Give reasons:
   (a) A gas fills completely the vessel in which it is kept.
   (b) A gas exerts pressure on the walls of the container.
   (c) A wooden table should be called a solid.
   (d) We can easily move our hand in the air but to do the same through a solid block of wood we need a karate expert. 
8.  Liquids generally have lower density as compared to solids. But you must have observed that ice floats on water. Find out why.
9. Convert the following temperature to Celsius scale: (a) 300 K,  (b) 573 K. 
10. What is the physical state of water at (a) 25ºC,  (b) 100ºC? 
11. For any substance, why does the temperature remain constant during the change of state? 
12. Suggest a method to liquefy atmospheric gases.
13. Why does a desert cooler cool better on a hot dry day? 
14. How does the water keep in an earthen pot (Matka) become cool during summer? 
15. Why does our palm feel cold when we put some acetone or petrol or perfume on it? 
16. Why are we able to sip hot tea or milk faster from a saucer rather than a cup? 
17. What type of clothes should we wear in summer?
18. Convert the following temperatures to the Celsius scale. 
    (a) 300 K, (b) 573 K.
19. Convert the following temperatures to the Kelvin scale. 
    (a) 25°C, (b) 373°C. 
20. Give the reason for the following observations.
    (a) Naphthalene balls disappear with time without leaving any solid.
    (b) We can get the smell of perfume sitting several meters away. 
21. Arrange the following substances in increasing order of forces of attraction between the particles— water, sugar, oxygen. 
22. What is the physical state of water at— 
    (a) 25°C (b) 0°C (c) 100°C ? 
23. Give two reasons to justify—
    (a) water at room temperature is a liquid.
    (b) an iron almirah is a solid at room temperature.
24. Why is ice at 273 K more effective in cooling than water at the same temperature? 
25. What produces more severe burns, boiling water or steam?

CHAPTER 1 - MATTER IN OUR SURROUNDINGS	☛ QUESTION WITH SOLUTIONS
CHAPTER 2 - IS MATTER AROUND US PURE?	☛QUESTION WITH SOLUTIONS
CHAPTER 3 - ATOMS AND MOLECULES	☛ QUESTION WITH SOLUTIONS
CHAPTER 4 - STRUCTURE OF ATOM	☛   QUESTION WITH SOLUTIONS
CHAPTER 5 -  THE FUNDAMENTAL UNIT OF LIFE
CHAPTER 6 -  TISSUE
CHAPTER 7 -   DIVERSITY IN LIVING ORGANISM
CHAPTER 8 -  MOTION	☛ QUESTION WITH SOLUTIONS
CHAPTER 9 -  FORCE AND LAW OF MOTION	☛  QUESTION WITH SOLUTIONS
CHAPTER 10 - GRAVITATION	☛ QUESTION WITH SOLUTIONS
CHAPTER 11 -  WORK AND ENERGY
CHAPTER 12 -  SOUND
CHAPTER 13-  WHY DO WE FALL ILL
CHAPTER 14 - NATURAL RESOURCES
CHAPTER 15 - IMPROVEMENT OF FOOD RESOURCES