X- chemistry Guess Test paper - Ch -5-Periodic-Classification-of-Elements

1. “Elements in Periodic Table show periodicity of properties” List any four such properties.

2. The following table shows the positions of six elements A, B, C,D,E and F in the modern periodic table

Group\Period	1	2		3to 12	13		14	15	16	17	18
2	A							B				C
3		D					E					F

(a). Which element will form only covalent compounds ?  

(b)  Which element is a metal with valency two ?

(c). Out of D and E , which one has a bigger atomic radius ? Give reason for your answers. 

3. (a) Atomic number of Mg and Al are 12 and 13 respectively. Write their electronic configuration. 
(b) Mention the period of the Modern Periodic Table to which the above two elements belong. Give reason for your answer

4. (a) State the Modern periodic law. (b) What is the total number of periods and groups in Modern Periodic Table
5. From the part of a periodic table, answer the following questions

1 Hydrogen	2	13	14 Carbon			15	16 Oxygen		17 Fluorine
X				P				Q
Y								R
Z								T

(a) Atomic number of oxygen is 8. What would be the atomic number of, Fluorine ?

(b) Out of ‘X’ and ‘Q’ which element has larger atomic size. Give reason for your answer Fluorine.

(c) Out of ‘Y’ and ‘Z’ which element has smaller atomic size. Give reason for your answer.

6. State two limitations of Newland's law of Octaves.

7. Name the scientist who proposed modern periodic law? On which fundamental property of elements it is based?
8. Why could no fixed position be given to hyderogen in Mendleev’s Periodic table?

9. What are metalloids? Give two examples.

10. In group 1 of periodic table three elements X, Y and Z have atomic radii 133pm , 95pm and 65pm respectively giving a reason, arrange them in the increasing order of their atomic number in the group.

11. In modern periodic table, the isotopes of Chlorine Cl-35 and Cl-37 having different atomic masses will be kept in different slots or they would be assigned same position on the basis of their chemical properties? Give reason in support of your answer.

12. Nitrogen (At no. 7) and Phosphorus (At no. 15) belong to group 15 of the periodic table:-

13. How and why does the atomic size vary as you go down a group?

14. Why was Dobereiner’s system of classification of elements into triads not found to be useful?

15.(a) “Silicon is classified as a metalloid.” Justify this classification.

(b) Name two more such metalloids.

(c) In which part of the Periodic Table we can look for metalloids. On which side of these we can get non- metals ?