Advertisements
Advertisements
प्रश्न
F, Cl and Br are the elements each having seven valence electrons. Which of these (i) has the largest atomic radius, (ii) is most reactive? Justify your answer stating reason for each.
उत्तर
(i) F, Cl, Br belong to same group 17. Atomic size increase down the group. This is because new shells are added. Hence, Br has largest atomic radius because it has a shells compared to 3 and 2 in Cl and F respectively.
(ii) F is most reactive due to smaller size, high effective nuclear charge and high electro negativity.
संबंधित प्रश्न
An element 'X' belong to 3rd period and group 13 of the Modern Periodic Table.
(a) Determine the valence electrons and the valency of 'X'.
(b) Molecular formula of the compound formed when 'X' reacts with an element 'Y' (atomic number = 8).
(c) Write the name and formula of the compound formed when 'X' combines with chlorine
Choose the most appropriate answer of the following:
Which of the following would weigh the least?
(A) 2-gram atoms of Nitrogen.
(B) 1mole of Silver
(C) 22.4 liters of oxygen gas at 1 atmospheric pressure and 273K
(D) 6.02 x 1023 atoms of carbon.
[Atomic masses: Ag=108, N=14, O=16, C=12]
Fill in the blank in the following statement:
On going down in a group in the periodic table, the metallic character of elements ...............
Given alongside is a part of the periodic table. As we move vertically downward from Li to Fr:
| Li | Be |
| Na | |
| K | |
| Rb | |
| Cs | |
| Fr | Ra |
What happens to their metallic character?
Name the element of lower nuclear charge out of Be and Mg.
State the nature of compounds formed when group 17 elements combine with (i) metals (ii) non-metals.
Name or state following with reference to the element of the first three periods of the periodic table.
The formula of the hydroxide of the element having electronic configuration 2, 8, 2.
Name or state following with reference to the element of the first three periods of the periodic table.
The valency of the element in period 3 having atomic number 17.
Fill in the blanks from the words A to F given below.
A: Decreases
B: Increases
C: Remains same
D: Increases by one
E: Electropositive
F: Electronegative
Down a group in the Modern Periodic Table.
No. of electron shells __________; No. of valence electrons ________; Electronegativity ________ Character of elements changes from _________ to ____________.
