State whether the statements given below are True or False.
(i) Stone is transparent, while glass is opaque.
(ii) A notebook has lustre while eraser does not.
(iii) Chalk dissolves in water.
(iv) A piece of wood floats on water. (v) Sugar does not dissolve in water.
(vi) Oil mixes with water.
(vii) Sand settles down in water.
(viii) Vinegar dissolves in water.
(i) False
Stone is not an transparent object because it does not allow light to pass through it. While glass is transparent because it allows light to pass through it.
(ii) False
This statement is false because notebook and eraser both are not metals. So, they both do not contain luster.
(iii) False
Chalk does not dissolve in water because if this get dissolved in water it makes colloidal solution or we can say that it makes an heterogeneous mixture.
(iv) True
Wood floats on water because wood have less density than water.
(v) False
Because sugar dissolves in water and makes a saturated solution.
(vi) False
It is a false statement because oil has less density than water. So oil floats on water but do not mix with water. Oils are non- polar whereas water is polar. But both are immiscible liquids.
(vii) True
This statement is true because when sand mixes in water it makes colloidal solution and when this solution is left undisturbed it settles down in the bottom.
(viii) True
Because vinegar makes a homogeneous mixture or solution when mixes with water.
List all items known to you that float on water. Check and see if they will float on an oil or kerosene.
Given below are the names of some objects and materials:
Water, basket ball, orange, sugar, globe, apple and earthen pitcher Group them as:
(a) Round shaped and other shapes
(b) Eatables and non eatables
Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a
given material could be used for making many objects.
Objects Materials
Book Glass
Tumbler Wood
Chair Paper
Toy Leather
Shoes Plastics
Find the odd one out from the following:
a) Chair, Bed, Table, Baby, Cupboard
b) Rose, Jasmine, Boat, Marigold, Lotus
c) Aluminium, Iron, Copper, Silver, Sand
d) Sugar, Salt, Sand, Copper sulphate
Select those objects from the following which shine:
Glass bowl, plastic toy, steel spoon, cotton shirt
Name five objects which can be made from wood.
(a) Which kind of garbage is not converted into compost by the redworms?
(b) Have you seen any other organism besides redworms, in your pit? If yes, try to find out their names. Draw pictures of these.
Rearrange the boxes given below to make a sentence that helps us understand opaque objects.
To walk through a waterlogged area, you usually shorten the length of your dress by folding it. Can this change be reversed?
Do you find that all living beings need the same kind of food?
Name the major nutrients in our food.
Classify the following fibres as natural or synthetic:
nylon, wool, cotton, silk, polyester, jute
Why do we need to separate different components of a mixture? Give two examples.
Correct the following statements and rewrite them in your notebook.
(a) Stem absorbs water and minerals from the soil.
(b) Leaves hold the plant upright.
(c) Roots conduct water to the leaves.
(d) The number of petals and sepals in a flower is always equal.
(e) If the sepals of a flower are joined together, its petals are also joined together.
(f) If the petals of a flower are joined together, then the pistil is joined to the petal.
Fill in the blanks:
(a) Joints of the bones help in the ——————— of the body.
(b) A combination of bones and cartilages forms the _______ of the body.
(c) The bones at the elbow are joined by a ______________________ joint.
(d) The contraction of the _____________ pulls the bones during movement.
What is a habitat?
Complete the drawing shown in Fig 12.14 to indicate where the free ends of the two wires should be joined to make the bulb glow.
A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilised. Can the change in POP be reversed?
Name the major nutrients in our food.
What is a habitat?
Match the items given in Column A with that in Column B
Column A Column B
Milk, curd, paneer, ghee eat other animals
Spinach, cauliflower, carrot eat plants and plant products
Lions and tigers are vegetables
Herbivores are all animal products
To clean their spectacles, people often breathe out on glasses to make them wet. Explain why the glasses become wet.
Arrange the following lengths in their increasing magnitude:
1 metre, 1 centimetre, 1 kilometre,1 millimetre.
Using the "conduction tester" on an object it was found that the bulb begins to glow. Is that object a conductor or an insulator? Explain.
Can you find a plant in your house or in your neighborhood, which has a long but a weak stem? Write its name. In which category would you classify it?
Fill in the blanks:
(a) Joints of the bones help in the ——————— of the body.
(b) A combination of bones and cartilages forms the _______ of the body.
(c) The bones at the elbow are joined by a ______________________ joint.
(d) The contraction of the _____________ pulls the bones during movement.