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Introduction

The Lewis model of chemical bonding is one of the most powerful models in all of Chemistry. With the simple concepts of the octet rule and the sharing of an electron pair to form a chemical bond, we can predict what combinations of atoms and which molecular structures are likely to be stable or unstable. For example, we can predict that the molecular formula C 4 H 10 should correspond to a stable molecular structure, since it possible to draw a Lewis structure in which all four carbon atoms have an octet of valence electrons and each hydrogen atom has two valence electrons. In fact, we can even predict that there should be two such molecular structures corresponding to two different stable compounds, butane and methyl propane (often called isobutane). Lewis structures also allow us to predict the relative strengths and lengths of chemical bonds. For example, we can predict that in the molecule propene C 3 H 6 , one of the C-C bonds is a single bond and the other is a double bond; correspondingly, we can predict that the double bond is shorter and stronger than the single bond.

In general, for any molecule containing some combination of atoms of C, N, H, O, and any of the halogens (F, Cl, Br, or I), we can predict with confidence that the molecule will be a stable compound if we can draw a Lewis structure in which the C, N, O, and halogen atoms all have an octet of valence electrons. This is a very significant statement, since the overwhelming majority of the molecules of organic chemistry are composed of only these atoms. The converse is also generally true: if we cannot draw a Lewis structure in which these atoms have an octet of valence electrons, we will predict fairly confidently that a stable compound of that molecular formula probably does not exist. Note that “stable” does not mean “non-reactive.” In this context, “stable” means that the compound exists and can be isolated for long periods of time. Methane CH 4 is a stable compound which can be manufactured, captured, stored, and transported. However, it is also a reactive compound, reacting rapidly with oxygen gas in one of the most common combustion reactions in the world.

These are the reasons why we say that the Lewis structure model of covalent bonding is one of the most important models in all of Chemistry. However, like most good models, the understanding we get from the model comes with even more questions we might want to ask. In this Concept Development Study, we will address several of these, while others will wait for later studies. First, why does sharing a pair of electrons create a chemical bonding? More pointedly, what does it even mean to “share” an electron between two atoms? And why do atoms prefer to share a pair of electrons, rather than one or three? Of course, we’ve also seen that atoms can share more than one pair of electrons, creating double or triple bonds. We might have guessed that, with more electrons being shared, these electrons would repel each other, leading to a higher energy, but this is not the case. Why does sharing more than one pair of electrons produce a stronger bond?

Questions & Answers

show that the set of all natural number form semi group under the composition of addition
Nikhil Reply
explain and give four Example hyperbolic function
Lukman Reply
_3_2_1
felecia
⅗ ⅔½
felecia
_½+⅔-¾
felecia
The denominator of a certain fraction is 9 more than the numerator. If 6 is added to both terms of the fraction, the value of the fraction becomes 2/3. Find the original fraction. 2. The sum of the least and greatest of 3 consecutive integers is 60. What are the valu
SABAL Reply
1. x + 6 2 -------------- = _ x + 9 + 6 3 x + 6 3 ----------- x -- (cross multiply) x + 15 2 3(x + 6) = 2(x + 15) 3x + 18 = 2x + 30 (-2x from both) x + 18 = 30 (-18 from both) x = 12 Test: 12 + 6 18 2 -------------- = --- = --- 12 + 9 + 6 27 3
Pawel
2. (x) + (x + 2) = 60 2x + 2 = 60 2x = 58 x = 29 29, 30, & 31
Pawel
ok
Ifeanyi
on number 2 question How did you got 2x +2
Ifeanyi
combine like terms. x + x + 2 is same as 2x + 2
Pawel
x*x=2
felecia
2+2x=
felecia
Mark and Don are planning to sell each of their marble collections at a garage sale. If Don has 1 more than 3 times the number of marbles Mark has, how many does each boy have to sell if the total number of marbles is 113?
mariel Reply
Mark = x,. Don = 3x + 1 x + 3x + 1 = 113 4x = 112, x = 28 Mark = 28, Don = 85, 28 + 85 = 113
Pawel
how do I set up the problem?
Harshika Reply
what is a solution set?
Harshika
find the subring of gaussian integers?
Rofiqul
hello, I am happy to help!
Shirley Reply
please can go further on polynomials quadratic
Abdullahi
hi mam
Mark
I need quadratic equation link to Alpa Beta
Abdullahi Reply
find the value of 2x=32
Felix Reply
divide by 2 on each side of the equal sign to solve for x
corri
X=16
Michael
Want to review on complex number 1.What are complex number 2.How to solve complex number problems.
Beyan
yes i wantt to review
Mark
use the y -intercept and slope to sketch the graph of the equation y=6x
Only Reply
how do we prove the quadratic formular
Seidu Reply
please help me prove quadratic formula
Darius
hello, if you have a question about Algebra 2. I may be able to help. I am an Algebra 2 Teacher
Shirley Reply
thank you help me with how to prove the quadratic equation
Seidu
may God blessed u for that. Please I want u to help me in sets.
Opoku
what is math number
Tric Reply
4
Trista
x-2y+3z=-3 2x-y+z=7 -x+3y-z=6
Sidiki Reply
can you teacch how to solve that🙏
Mark
Solve for the first variable in one of the equations, then substitute the result into the other equation. Point For: (6111,4111,−411)(6111,4111,-411) Equation Form: x=6111,y=4111,z=−411x=6111,y=4111,z=-411
Brenna
(61/11,41/11,−4/11)
Brenna
x=61/11 y=41/11 z=−4/11 x=61/11 y=41/11 z=-4/11
Brenna
Need help solving this problem (2/7)^-2
Simone Reply
x+2y-z=7
Sidiki
what is the coefficient of -4×
Mehri Reply
-1
Shedrak
A soccer field is a rectangle 130 meters wide and 110 meters long. The coach asks players to run from one corner to the other corner diagonally across. What is that distance, to the nearest tenths place.
Kimberly Reply
Jeannette has $5 and $10 bills in her wallet. The number of fives is three more than six times the number of tens. Let t represent the number of tens. Write an expression for the number of fives.
August Reply
What is the expressiin for seven less than four times the number of nickels
Leonardo Reply
How do i figure this problem out.
how do you translate this in Algebraic Expressions
linda Reply
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Concept development studies in chemistry 2013. OpenStax CNX. Oct 07, 2013 Download for free at http://legacy.cnx.org/content/col11579/1.1
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