Advertisements
Advertisements
प्रश्न
The elements A, B, C, D and E have atomic numbers 9, 11, 17, 12 and 13 respectively. The pair of elements which belongs to the same group of the periodic table is:
(a) A and B
(b) B and D
(c) A and C
(d) D and E
उत्तर
(c) A and C
Electronic configuration of A (9) : K L
2 7
Electronic configuration of C (17): K L M
2 8 7
Group number of A and B = valence electron + 10
= 7+10 = 17.
APPEARS IN
संबंधित प्रश्न
Which element has twice as many electrons in its second shell as in its first shell?
Fill in the blank in the following statement:
In going across a period (right to left) in periodic table, the atomic size of the atom ...............
What happens to the metallic character of the elements as we move from left to right in a period of the periodic table?
How does the tendency to gain electrons change as we go down in group 17 of the periodic table? Why does it change this way?
Five elements A, B, C, D and E have atomic numbers of 2, 3, 7, 10 and 18 respectively. The elements which belong to the same period of the periodic table are:
(a) A, B, C
(b) B, C, D
(c) A, D, E
(d) B, D, E
The atomic numbers of the elements Na, Mg, K and Ca are 11, 12, 19 and 20 respectively. The element having the largest atomic radius is:
(a) Mg
(b) Na
(c) K
(d) Ca
Which of the following is the valence shell for the elements of second period of the modern periodic table?
(a) M shell
(b) K shell
(c) L shell
(d) N shell
With reference to the variation of properties in the Periodic table, which of the following is generally true?
Element P has atomic number 19. To which group and period, does P belong? Is it a metal or a non-metal? Why?
What is the common feature of the electronic configuration of the elements at the end of Period 2 and Period 3?
