SCHOOL OF ELEMENTS OBJECTIVES
Fill in the blanks :
1. The horizontal rows in the periodic table are ................ .
2. From left to right, the atomic size of an atom................. .
3. There are ............... periods in the periodic table.
4. An element is placed in group II A, so the number of valence electrons is ..............
5. An element is placed in 2nd period, so it has ....................... shells.
6. Noble gases have valency as ....................... 7. Metals have a tendency to ....................... electrons..
8. Valency across a period ....................... .
9. Valency down the group ....................... .
10. Elements of group I A and II A are ....................... .
11. An atom is said to be a non-metal if it .................... electrons.
12. ....................... is the only element in duplet state.
13. The electronic configuration of Neon is ....................... .
14. Sodium is a ....................... .
15. Silicon and antimony are ....................... .
16. Group 1A is called ....................... .
17. Group II A is called as ....................... .
18. Group VII A is called as ....................... .
19. The chemical properties down the group ................... .
20. First period contains .................. elements.
21. Moseley arranged elements according to .................. .
22. The non-metals are present in.............. .
23. The number of shells down the group ....................... .
24. The transition character of elements is from……… to .............. .
*25. The formula of chloride of metal is MCl2 , the metal M belongs to ....................... group.
*26. ....................... group contains all gases at room temperature.
*27. The arrangement of elements in a group of three is called ....................... .
*28. The law used by Newlands to arrange elements is called ....................... .
*29. Elements showing properties of both metals and non-metals are called as................
*30. The element eka-Aluminium is called as ....................... .
ANSWERS
A. Answers.
1. Periods
2. Decreases
3. 7
4. 2
5. 2
6. 0
7. Donate
8. Varies gradually
9. Remains the same
10. Metals
11. Gains or shares
12. Helium
13. 2,8
14. Metal
15. Metalloids
16. Alkali metals
17. Alkaline earth metals
18. Halogens
19. Remain the same
20. 2
21. Atomic number
22. Upper right hand corner
23. Increases
24. Metallic to non – metallic
25. IIA
26. 18 or zero
27. Triad
28. Newlands Law of octaves
29. Metalloids
30. Gallium
