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Answer:</h2>
Valance electrons can be determined by <u>Group</u> on the periodic table
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Explanation:</h2>
- Valence electrons are the electrons present in the outermost shell of an atom. We can determine the total number of valence electrons present in an atom by checking at its Group in which it is placed in the periodic table. For example, atoms in Groups 1 the number of valence electron is one and for group 2 the number of valence electrons is 2.
- The groups have number of valance electrons as follow:
Group 1 - 1 valence electron.
Group 2 - 2 valance electrons.
Group 13 - 3 valence electrons.
Group 14 - 4 valance electrons.
Group 15 - 5 valence electrons.
Group 16 - 6 valence electrons.
Group 17 - 7 valence electrons.
Group 18 - 8 valence electrons.
Result: No of valence electron can be determined by the group no. of the element.
Answer:
B extinction
Explanation:
as the species does not exist any more, the species is extinct, therefore making the pictured fossil of an extinct species
hope this helps
Answer : The given compound belongs to ether and alcohol.
Explanation :
The chemical formula of the given compound is, 
First we have to calculate the degree of unsaturation.
Formula used:
Degree of unsaturation = 
where,
C = number of carbon
H = number of hydrogen
N = number of nitrogen
X = number of halogen
Degree of unsaturation = 
The degree of unsaturation is, 0 that means there is no double or triple bond in the compound only single bond is present between the atoms.
Thus, the given compound belongs to ether and alcohol.