Here is the answer for the three of them
<span>N20 = 16 e-
</span><span>SeCl2 =20
</span><span>PBr3 = 26
Remember that t</span><span>o find the valence electrons in an atom you need to identify what group the element is in. An element in group 1A has 1 valence electron. If the element is in group 2A, then it has two valence electrons.</span>
Answer: Electronegativity increases as the size of an atom decrease.
Explanation: Electronegativity is the measure of the ability of an atom in a bond to attract electrons to itself.
Electronegativity increases across a period and decreases down a group.
Towards the left of the table, valence shells are less than half full, so these atoms (metals) tend
to lose electrons and have low electronegativity. Towards the right of the table, valence shells are more than half full, so these atoms (nonmetals) tend to gain electrons and have high electronegativity.
Down a group, the number of energy levels (n) increases, and so does the distance between the nucleus and the outermost orbital. The increased distance and the increased shielding weaken the nuclear attraction, and so an atom can’t attract electrons as strongly.
The individual numbers which are present in chemical formula is subscript.
<h3>What is chemical formula?</h3>
Chemical formula of any compound of chemistry consist more than one atoms in it and gives idea about the number of atoms present in that compound.
Given chemical formula of glucose is C₆H₁₂O₆.
In the given chemical formula of glucose, number which shows the amount of carbon, hydrogen and oxygen are known as subscripts.
Hence, individual number are subscript.
To know more about chemical formula, visit the below link:
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Forms when lava and magma cool (A)
Answer:
I don't wanna intrigue but I think this is how you want things to go. But to make it easier all you have to do is look up "what is genomics" and then simply answer each question should take maybe 5-7 minutes. Just trying to help :)
