NCERT SOLUTION CLASS 9 SCIENCE CHAPTER

NCERT SOLUTION SCIENCE CLASS 9 CHAPTER 1 ( MATTER IN OUR SURROUNDINGS)

PAGE -3

QUESTION No 1

    Which of the following are matter?
    Chair,air,love,smell,hate,almonds,thought,cold,cold drink,smell of perfume.

ANSWER   

   SOLID STATE:       Chair and almond.
   LIQUID STATE:      Cold drink
   GASEOUS STATE :  Air and smell of perfume

QUESTION NO 2:     

  Give reason 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.

ANSWER: 

      Solids diffuses at a very slow rate. But if the temperature of a solid is increased then the particle of solids moves faster due to increased kinetic energy and thus diffusion of the solid particle increased in air. Hence .the smell of hot sizzling food reaches us even at a distance,but to get the smell from cold food you have to go close.

QUESTION NO 3

    A diver is able to cut through water in a swimming pool. Which property of matter does this observation show?

ANSWER:

     The ability of a diver to cut through water in a swimming pool show that matters is made up of particles.

QUESTION NO 4:

    What are the characteristics of the particles of matter?

ANSWER:

  The characteristics of particles of matter are -
1. Matter is made up of small particles.
2. Particles of matter have space between them.
3. Particles of matter are continuously moving.
4. Particles of matter attract each other.

 ALSO SEE THE SOLUTION OF PAGE-9 OF MATTERS IN OUR SURROUNDINGS