Chemistry
An element belongs to the 3rd period and Group IIIA (13) of the periodic table. State
(a) the number of valence electrons,
(b) the valency,
(c) if it is a metal or non-metal?
(d) the name of the element.
Answer
(a) 3, as the electronic configuration of the element is 2,8,3.
(b) +3, as the element will try to donate three valence electrons and attain a stable octet configuration.
(c) Metal, as the element has 3 valence electrons and tries to donate it to attain a stable configuration.
(d) Aluminium (Al), as it is in 3rd period and Group IIIA (13)
Related Questions
Arrange the following
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(b) Elements of group 17, in decreasing order of reactivity.
(c) He, Na, Mg (decreasing order of valency).
(d) Chlorine, sodium, magnesium (increasing reducing character).
Element P has atomic number 19. To which group and period, does P belong? Is it a metal or a non-metal? Why?
An element A has 2 electrons in its fourth shell. State:
(a) its atomic number
(b) its electronic configuration
(c) its valency
(d) position in the periodic table
(e) is it a metal or a non-metal?
(f) is it an oxidising or reducing agent?
(a) Name the first three alkaline earth metals.
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