Important Question with solution:
Que1: what do you mean by classification?
Ans: Classification is the grouping or sorting together of thing possesing similar or dissimilar characteristics or properties.
Que2: what is the need for classification?
Ans: Classification is essential for:
- identification of objects.
- sorting of objects.
- locating things.
- understanding similarties and dissimailarities among objects.
- making the object easy and more meaningful.
Que3: why is mercury used in making thermometers?
Ans:
- Mercury is liqid 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.
Que4: Why do we need the grouping of object?
Ans: Group the object helps us to arrange them in a systematic manner. The object when ground are easy to hanble. When grouded, it is easy to know the properties of an object clearly. Grouping also makes easy to compare two objects.
Que5: Why is what important for our body?
Ans: Water can dissolve a large number of substances, so it is needed by the body. it is also major part os our bosy cells.
Que6: List five eacgh opaque and transparent materials?
Ans: Opaque materials:
- Wood
- Iron
- Cardboard
- Brick
- Gold
Transparent materials:
- Water
- Glass
- Air
- Cellophine plastic and
- fibre glass.
Que7: Why is water called unversal solvent?
Ans: The property of water to dissolve large number of materials makes it a universal solvent.
Que8: State conditions when pure water can lose transparency?
Ans: water on cooling, freezes to from ice which is not transparent.
Que9: Why is a tumbler not made with a piece of cloth?
Ans: The is beacuse we generally use a tumbler to keep a liquid. A tumbler made of a piece of cloth cannot be keep water. So, a tumbler is made with a material which has a property to hold the liquid.
Que10: Name two gases each which are soluble and insoluble in water.
Ans: Gases soloble in water are Oxyen and carbon dioxide. Gases insoluble in water are hydrogen and nitrogen.
