Concept explainers
Interpretation:
Lewis structures for the given compounds are to be drawn.
Concept introduction:
The octet rule states that every element in the main group should have eight electrons in its valence shell in order to attain a noble gas configuration.
Valence electrons are those electrons thatoccupy the last shell of an element.
Lewis dot symbols contain dots, which give information about valence electrons.
Lewis structures show bonds as lines and lone pairs as dots.
In Lewis dot
In Lewis dot symbol, valence electrons are represented by dots.
Dots are placed above and below as well as to the left and right of symbol.
Number of dots is important in Lewis dot symbol but not the order in which the dots are placed around the symbol.
In writing symbol pairing is not done until absolutely necessary.
For metals, the number of dots represents the number of electrons that are lost when the atom forms a cation.
For second period nonmetals, the number of unpaired dots is the number of bonds the atom can form.
Atomic ions can also be represented by dot symbols, by simply adding (for anions) and subtracting (for cations) the appropriate number of dots from Lewis dot symbol.
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Chemistry
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