Q 1 – Which of the following floats on water?
(a) Wax
(b) Marble
(c) Coin
(d) Eraser
(a) Wax
Q 2 – Which of the following is a matter?
(a) Air
(b) Steel
(c) Water
(d) All of these
(d) All of these
Q 3 – Anything that has a mass and occupies space is called
(a) classification
(b) volume
(c) matter
(d) air
(c) matter
Q 4 – Which of the following has a fixed shape?
(a) Iron
(b) Oxygen
(c) Milk
(d) CO2
(a) Iron
Q 5 – Which gas is responsible for fizz in soft drinks?
(a) Oxygen
(b) Hydrogen
(c) Nitrogen
(d) Carbon dioxide
(d) Carbon dioxide
Q 6 – Tables are made up of
(a) plastic
(b) wood
(c) leather
(d) none of these
(d) none of these
Q 7 – Which one of the following liquids is immiscible with water?
(a) Vinegar
(b) Glycerine
(c) Lemon juice
(d) Kerosene
(d) Kerosene
Q 8 – Fill in the blanks:
- Wood is ………….. than rubber.
- Heavy substances ………….. in water.
- Earthen pitcher is an example of ………….. object.
- Materials that have lustre are usually …………..
- An object can be made of different …………..
- Harder
- sink
- round
- metals
- materials
Q 9 – True or false
- Solids have neither a definite shape nor volume.
- A hard substance can scratch a soft substance.
- Grouping is a useful process.
- Things made of gold and aluminium have no lustre.
- All materials can be felt by one or more of our senses.
- False
- True
- True
- False
- True
Q 10 – Match the Following
Column I | Column II |
1. Glass, air | (a) Translucent |
2. Wax | (b) Belt, Shoes |
3. Oiled paper | (c) Floats on water |
4. Copper sulphate | (d) Transparent |
5. Wood | (e) Soluble |
6. Leather | (f) Insoluble |
7. Diamond | (g) Metallic lustre |
8. Chalk powder | (h) Opaque |
9. Sponge | (i) Hard |
10. Gold and silver | (j) Soft |
Column I | Column II |
1. Glass, air | (d) Transparent |
2. Wax | (c) Floats on water |
3. Oiled paper | (a) Translucent |
4. Copper sulphate | (e) Soluble |
5. Wood | (h) Opaque |
6. Leather | (b) Belt, Shoes |
7. Diamond | (i) Hard |
8. Chalk powder | (f) Insoluble |
9. Sponge | (j) Soft |
10. Gold and silver | (g) Metallic lustre |
Q 11 – ‘Grouping of objects helps the shopkeeper.’ Justify the statement.
Ans. Proper grouping of objects helps shopkeeper in the following ways:
(i) He can locate the required object easily and quickly.
(ii) He can easily come to know what stocks are going to finish and he should purchase them for his customers.
Q 12 – What is a translucent material?
Translucent materials are those that allow objects to be seen but not clearly. For example, Sunglasses, Butter paper.
Q 13 – Name two gases that are soluble and insoluble in water.
Oxygen and carbon dioxide are soluble gases in water. Hydrogen and nitrogen are insoluble in water.
Q 14 – Why is water essential for our bodies?
Water is essential for our bodies because it can dissolve a good range of substances required by the body. It is also an important component of our body’s cells.
Q 15 – Why is mercury used in making thermometers?
- Mercury is liquid at room temperature.
- It is a good conductor of heat.
- Mercury has lustre, so, it is easy to read the temperature shown by the level of mercury.
Q 16 – Why do shopkeepers prefer to keep eatables in transparent containers?
Shopkeepers usually keep biscuits, sweets, and other eatables in glass or transparent containers so that customers can easily see them.
Q 17 – Show that sugar, common salt and washing soda are soluble while chalk powder, iodine and sand are insoluble in water.
Take six test tubes, fill each of them about half with water. Keep each of them in a test tube stand. Add a pinch of each of six substances in separate test tubes. Shake well and allow to stand for few minutes. Common salt, sugar and washing soda dissolve while iodine, chalk powder and sand do not dissolve.
Q 18 – Why do some metals dull and lose their lustre?
Some metals lose their lustre and become dull because they react with the gases and moisture in the air, forming a thin layer of oxide, carbonate, or sulphide.
Q 19 – Describe an experiment that demonstrates that the palm is translucent.
The steps in the experiment are as follows:
- In a dark place, cover the glass of a torch with your palm.
- Turn on the torch.
- Look at the light from the opposite side of the palm.
The palm allows some light to pass through it, but not all of it. This demonstrates that our palm is translucent.
Q 20 – What is the significance of dissolved oxygen gas in water?
Some gases are soluble in water, whereas others are insoluble. Water dissolves oxygen gas. The oxygen dissolved in water is used for respiration by plants and animals that live in water. Thus, oxygen dissolved in water is critical for the survival of aquatic animals and plants.
Q 21 – Describe an experiment to prove that water is transparent.
Take a beaker half-filled with clean water. Put a coin in beaker of water.
Place the beaker undisturbed for a few minutes where enough light is present. Now, observe the coin immersed in water from the top of the beaker. Are you able to see the coin? You can clearly see the coin immersed in water. This proves that water is a transparent liquid.
Q 22 – According to the property of hardness, how would you differentiate whether the object is soft or hard? Justify your answer.
When you press different materials with your hands, some of them may be hard to compress while others can be easily compressed. Take a metal key and try to scratch with it, the surface of a piece of wood, aluminium, a piece of stone, a nail, candle, chalk, any other material or object.
You can easily scratch some materials, while some cannot be scratched so easily. Materials which can be compressed or scratched easily are called “soft” while some other materials which are difficult to compress are called “hard”. For example, cotton or sponge is soft while iron is hard.
Q 23 – How does appearance of objects help us to make sort out of different materials? Show with an activity.
Collect small pieces of different materials – paper, cardboard, wood, copper wire, aluminium sheet, chalk. Separate the shiny materials into a group. Now, cuts each material into two pieces and look at the freshly cut surface. Some of these materials are appear shiny. Include these objects also in the group of shiny materials.
Instead of cutting, you can rub the surface of material with sand paper to see if it has lustre. Materials that have such lustre are usually metals. Iron, copper, aluminium and gold are examples of metals. Therefore, we can differentiate the materials, according to the lustre.
Q 24 – How can materials be grouped together? In what ways do we classify materials?
Different materials have different properties. Materials with similar properties can be grouped together.
Different types of materials can be grouped based on any of the following properties:
- Appearance
- Solubility
- Transparency
- Conductivity
- Combustibility—Easily burn or not.
- Attraction towards magnet.