MATTER IN OUR SURROUNDINGS

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Created by
Jaza

Cards (65)

  • As we look at our surroundings, we see a large variety of things with different shapes, sizes and textures. Everything in this universe is made up of material which scientists have named "matter".
  • Examples of matter

    • Air we breathe
    • Food we eat
    • Stones
    • Clouds
    • Stars
    • Plants
    • Animals
    • Drop of water
    • Particle of sand
  • All the things mentioned occupy space and have mass. In other words, they have both mass and volume.
  • Panch Tatva
    Five basic elements according to early Indian philosophers - air, earth, fire, sky and water
  • According to early Indian philosophers, everything, living or non-living, was made up of these five basic elements.
  • Ancient Greek philosophers had arrived at a similar classification of matter.
  • Modern day classification of matter

    Based on physical properties and chemical nature
  • Activity 1.1: Dissolving salt/sugar in water
    1. Take a 100 mL beaker
    2. Fill half with water and mark level
    3. Dissolve salt/sugar with glass rod
    4. Observe any change in water level
    5. What happened to the salt?
    6. Where did it disappear?
    7. Did the water level change?
  • The activity shows that matter is made up of particles that can spread throughout the water.
  • Activity 1.2: Diluting potassium permanganate solution
    1. Take 2-3 crystals of potassium permanganate
    2. Dissolve in 100 mL water
    3. Take 10 mL of this solution and dilute in 90 mL water
    4. Keep diluting 5-8 times
    5. Observe if the water is still coloured
  • The activity shows that particles of matter are very small - they can be diluted extensively yet still be detected.
  • Activity 1.3: Detecting smell of incense stick

    1. Put an unlit incense stick in the corner
    2. Note how close you need to be to smell it
    3. Light the incense stick and note if you can smell it from a distance
  • The activity shows that particles of matter are continuously moving.
  • Activity 1.4: Diffusion of ink and honey in water

    1. Put a drop of ink/honey along the sides of two beakers of water
    2. Observe what happens immediately and over time
  • The activity shows that particles of matter continuously mix and spread out on their own, a process called diffusion.
  • Activity 1.5: Diffusion in hot and cold water
    1. Drop a crystal in hot and cold water
    2. Observe what happens just above the solid and over time
    3. Does the rate of mixing change with temperature?
  • The activities show that particles of matter are continuously moving, and this movement increases with temperature, leading to faster diffusion.
  • Characteristics of particles of matter
    • They have space between them
    • They are continuously moving (have kinetic energy)
    • They attract each other with varying forces
  • Activity 1.6: Comparing forces between particles

    1. Form human chains with different levels of particle interaction
    2. Observe which chain is easiest to break
  • The activity shows that particles of matter have forces of attraction between them, with varying strengths.
  • Activity 1.7: Comparing forces in different materials

    1. Try breaking an iron nail, chalk, and rubber band
    2. Observe which one requires more force
  • The activity shows that the force of attraction between particles varies in different materials.
  • Activity 1.8: Observing surface tension of water

    Try cutting the surface of water with your fingers
  • The activity shows that there is a force acting on the surface of water, keeping it together.
  • States of matter

    • Solid
    • Liquid
    • Gas
  • Activity 1.9: Observing properties of solids
    1. Collect a pen, book, needle, wooden stick
    2. Sketch their shapes
    3. Observe their definite shape, boundaries, volume, compressibility, rigidity
  • Solids have definite shape, boundaries, volume, and are rigid.
  • Activity 1.10: Observing properties of liquids

    1. Collect water, oil, milk, juice, cold drink
    2. Measure 50 mL in different containers
    3. Observe if the volume remains the same, if the shape changes, and if they flow easily
  • Liquids have no fixed shape but have a fixed volume, and can flow and change shape.
  • r

    When pressed, the air is expelled out and it can be compressed
  • Liquids

    • Have no fixed shape but have a fixed volume
    • Take up the shape of the container
    • Flow and change shape, so they are not rigid but can be called fluid
  • Solids, liquids and gases can diffuse into liquids
  • The rate of diffusion of liquids is higher than that of solids
  • This is due to the fact that in the liquid state, particles move freely and have greater space between each other as compared to particles in the solid state
  • Gases are highly compressible as compared to solids and liquids
  • Compressed natural gas (CNG) is used as fuel in vehicles due to its high compressibility
  • Gases show the property of diffusing very fast into other gases due to high speed of particles and large space between them
  • In the gaseous state, the particles move about randomly at high speed
  • The pressure exerted by the gas is because of the force exerted by gas particles per unit area on the walls of the container
  • On increasing the temperature of solids, the kinetic energy of the particles increases