Chemistry (Class X)(CBSE) Second term test paper on periodic classification of elements)

Class X (CBSE)

Second Term

 

PERIODIC CLASSIFICATION OF ELEMENTS:

 

Note: Question 1-3 are 1 mark each, Questions 4-10 are 2 marks each.

 

1.      What is general trend in atomic size as you move from left to right in a period?

2.      Why all the atoms of a period have different chemical properties?

3.      How many electrons are present in valence shell of Cl?

4.      What are the limitations of Dobernier’s classification?

5.      What are noble gases? Explain their characteristics?

6.      Write the electronic configuration of Na, O, F and C.

7.      Explain out of ‘Na’ and ‘K’ who is more electropositive in nature?

8.      Why atomic number of an element is more important than its mass number?

9.      Compare Na and K with respect to their valence, formula of their oxide and formula of their chloride.

10.  Atomic number of an element X is 17. Predict its valence and tell whether it is metal or non metal?