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Question
What happens to the metallic character of the elements as we move from left to right in a period of the periodic table?
Solution
The metallic (electropositive) character of the elements decreases as we move from left to right and the non-metallic (electronegative ) character increases in a period of the periodic table.
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RELATED QUESTIONS
Two elements ‘P’ and ‘Q’ belong to the same period of the modern periodic table and are in Group 1 and Group 2, respectively. Compare their following characteristics in tabular form:-
(a) The number of electrons in their atoms
(b) The sizes of their atoms
(c) Their metallic character
(d) Their tendencies to lose electrons
(e) The formula of their oxides
(f) The formula of their chlorides
The position of eight elements in the Modern Periodic Table is given below where atomic numbers of elements are given in the parenthesis.
| Period No. | ||
| 2 | Li(3) | Be(4) |
| 3 | Na(11) | Mg(12) |
| 4 | K(19) | Ca(20) |
| 5 | Rb(37) | Sr(38) |
(i) Write the electronic configuration of Ca.
(ii) Predict the number of valence electrons in Rb.
(iii) What is the number of shells in Sr?
(iv) Predict whether K is a metal or a non – metal.
(v) Which one of these elements has the largest atom in size?
(vi) Arrange Be, Ca, Mg and Rb in the increasing order of the size of their respective atoms.
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
An element 'X' has mass number 35 and number of neutrons 18. Write atomic number and electronic configuration of 'X'. Also write group number, period number and valency of 'X'.
Consider two elements 'X' (Atomic number 17) and 'Y' (Atomic number 20)
(i) Write the positions of these elements in the modern periodic table giving justification.
(ii) Write the formula of the compound formed by the combination of 'X' and 'Y'.
(iii) Draw the electron-dot structure of the compound formed and state the nature of the bond formed between the two elements ?
Rewrite the following statement after correction, if necessary:
The metallic character of elements in a period increases gradually on moving from left to right.
Explain why, the properties of elements are repeated after 2, 8, 18 and 32 elements in the periodic table.
How many groups and periods are there in the modern periodic table?
Arrange the following in order of increasing radii:
N, O, P
An element A has 2 electrons in its fourth shell. State:
is it a metal or non-metal
