Advertisements
Advertisements
Question
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
Solution
Period of X = 3
Group of X = 13
Atomic number of X = 13
Electronic configuration: 2, 8, 3
(a) Number of valence electrons = 3 and valency = 3
(b) Atomic number of Y = 8
Electronic configuration = 2, 6
Valency of Y = 2
Molecular formula of the compound formed when ‘X’ reacts with an element ‘Y’ is X2Y3.
(c) Atomic number of Cl = 17
Electronic configuration = 2, 8, 7
Valency of Y = 1
Molecular formula of the compound formed when ‘X’ reacts with an element ‘Y’ is XCl3
APPEARS IN
RELATED QUESTIONS
Name any two elements of group one and write their electronic configurations. What similarity do you observe in their electronic configurations? Write the formula of oxide of any of the aforesaid elements.
Name the element that has two shells, both of which are completely filled with electrons.
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?
What do you understand by periodicity?
State the valency of the elements of periods 3 and write the formula of their oxides.
An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.
Is it more or less reactive than calcium?
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.
What will be the valency of an element of atomic number 9 (nine)?
State whether the following statement is true or false
On moving horizontally across a period, number of valence electrons increases from one to eight.
Name the period which is the shortest period of the periodic table.
