Advertisements
Advertisements
Question
Define the term : Valency
Solution
Valency:-
The combining power or the combining capacity of an atom is called its valency. Valency of an atom is simply equal to the number of electrons gained, lost or shared by an atom to achieve the nearest noble gas configuration.
APPEARS IN
RELATED QUESTIONS
Given below are some elements of the modern periodic table. Atomic number of the element is given in parentheses.
A(4), B(9), C(14), D(19), E(20)
(a) Select the element that has one electron in the outermost shell. Also, write the electronic configuration of this element.
(b) Which two elements amongst these belong to the same group? Give reasons for your answer.
(c) Which two elements amongst these belong to the same period? Which one of the two has bigger atomic radius?
Calcium is an element with atomic number 20. Stating reason, answer each of the following questions:-
(i) Is calcium a metal or a non-metal?
(ii) Will its atomic radius be larger or smaller than that of potassium with atomic number 19?
(iii) Write the formula of its oxide.
Write the number of horizontal rows in the modern periodic table. What are these rows called?
Which element has the electronic configuration 2, 8, 2?
How does the number of valence electrons vary on moving from left or right in the first period of the periodic table?
The atomic radii of three elements X, Y and Z of a period of the periodic table are 186 pm; 104 pm and 143 pm respectively. Giving a reason, arrange these elements in the increasing order of atomic numbers in the period.
State the trends in physical properties on moving down the group. Give an example to illustrate.
Name the element in period 3 which does not form oxide.
Select the correct answer
Most reactive character among the elements given below is found in
Which of the following would weigh the least?
(Atomic masses C = 12, 0 = 16, Na = 23)