6 Substances in Daily Use

 Subject- Science ( Semi English)

    Std-6th.           J.V.Sonambe.

SubTeacher-Deepak Bhalerao,sir

SELF STUDY SERIES 

विद्यार्थी मित्रांनो,

खाली दिलेला स्वाध्याय नीट वाचा व आपल्या पुस्तकात पाहून उत्तरे लिहा.कोणतेही गाईड व व्यवसाय पुस्तिकांचा आधार घेऊ नका.

1) all substances are made up of very small ......

2) objects are made up of ......

3) the substances in everyday use or off tow main  kinds 1).......2)........substances

4) substances available in nature are called......

5) substances obtained from living things are called......

6) sand ,wool ,bamboo, cotton ,silk, leafy vegetables, fruits, water are....... substances

7) soap, window glass, bricks ,cement, sugar are ........substances

8) leather,wool ,jute, cotton are......substances

9) air, soil, water, metals are ..... substances 

10) leather and wool are of ..... origin 

11) jute and cotton are substances of...... origin 

12) new substances produced by processing naturally available substances are called ....... substances 

13) glass can be made from sand and ......

14) while making man made substances the properties of the constituents undergo a change. This change occurs due to certain chemical reactions.These changes in the properties are permanent,that is, the original constituent substances cannot be obtained again from the new substances such changes are called.....

15) rubber is of two types 1)

....... and 2).artificial

16) ........ invented the process of vulcanization of rubber

17) to give hardness to the rubber .....is mixed in it 

18) in rubber band the proportion of sulphur is very.....

19) rubber trees are found in abundance in......

20) in India the maximum production of rubber is in.     

21) paper is a kind of network of...... fibres 

22) paper and wood are closely related to save trees it is necessary to use..... sparingly 

23) in India the first factory to manufacture news print was established at...... in Madhya Pradesh 

24) in Maharashtra there is a paper factory at...... near Chandrapur 

25) ....... is a natural thread or fibre obtained from the cocoons of silk worms

26). It is said that silk was first produced on a large scale in.....

27). These threads were invented at the same time in New York and London. There fore the initials NY of New York and Lon from London were combined to name them......

28). Cotton and wood pulp is dissolved in a chemical called...... to make a solution 

29). They appeared to be shining bright like the sun's rays hence they were named....

30) various ......obtained from mineral oils are used to make polymer chains

31). Synthetic fibres are water repellent hence do not absorb sweet from the skin. Continuous use of clothes made from synthetic fibre threads keep the skin moist which may cause.....


टिप्पण्या