How is NO2 formed? N=2,5 needs to share 3 e- O=2,6 needs to share 2 e- how can 2 molecules of O share 3 e- and be stable, won't one molecule of O be unstable in order for Nitrogen to achieve an octet?

Yes Dishita, You are correct. One of the oxygen atom will be unstable. One of the oxygen will be able to complete its octet while the other oxygen cannot. Therefore NO2 is highly reactive!!

Why is the water molecule shaped like an inverted 'V' ? Why can't it be flat like Carbon dioxide ? Is it something to do with the covalent bonds? Also, do the electrons in the covalent bond stay between both atoms, or something else?

Well, the oxygen atom in the water molecule has 2 lone pairs of electrons(electrons that are not shared with other atoms). These electrons push away the bonded pairs of electrons,giving it its "V shape". In the case of carbon dioxide,however,the carbon atom has no lone pairs so there is no repulsion between the bonded pairs and lone pairs. For the second part of your question, the electrons are present in a 3D region around the nucleus of an atom. The electrons are not in a fixed position and are constantly moving around in the 3D region.

*Why is an octet so stable*?

The no. of valence electrons determine how reactive a substance is. An atom always tries to achieve the nearest noble gas electronic configuration (= valence electrons =octet except for atomic no. 1 to 5=duplet) an Octet (or duplet to those mentioned above) is the most stable electronic configuration of atoms as all orbitals will be full and don't have to gain,lose or share electrons. note: the max. no. of electrons in the outer shell is 8 If you're asking why *8 valence electrons* and not 6 or 20 or any other no., pardon I do not have the answer to that....yet

in the H2O lewis structure, wont the hydrogen atoms have a dash between them too? as they share an electron with each other

Not really. As you can see at 4:24 , hydrogen is not sharing electrons with each other, it is sharing electrons with oxygen. Which is why the formula of water is H2O, that is 1 atom of oxygen shares electrons with 2 atoms of hydrogen

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Course: Class 10 Chemistry (India) > Unit 4

Lesson 1: Bonding in carbon- covalent bond

Covalent bond and Lewis dot structure (H2O & CO2)

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Dishita
Posted 3 years ago. Direct link to Dishita's post “How is NO2 formed? N=2,5 ...”
How is NO2 formed?
N=2,5 needs to share 3 e-
O=2,6 needs to share 2 e-

how can 2 molecules of O share 3 e- and be stable,
won't one molecule of O be unstable in order for Nitrogen to achieve an octet?
Button navigates to signup pageComment on Dishita's post “How is NO2 formed? N=2,5 ...”
(7 votes)
Answer
- Somesh Sahu
  Posted 3 years ago. Direct link to Somesh Sahu's post “Yes Dishita, You are cor...”
  Yes Dishita,
  
  You are correct. One of the oxygen atom will be unstable. One of the oxygen will be able to complete its octet while the other oxygen cannot.
  Therefore NO2 is highly reactive!!
  Button navigates to signup page
  (4 votes)
ScienceLover7
Posted 4 years ago. Direct link to ScienceLover7's post “Why is the water molecule...”
Why is the water molecule shaped like an inverted 'V' ? Why can't it be flat like Carbon dioxide ? Is it something to do with the covalent bonds?
Also, do the electrons in the covalent bond stay between both atoms, or something else?
Button navigates to signup pageButton navigates to signup page
(3 votes)
Answer
- Aysha
  Posted 4 years ago. Direct link to Aysha's post “Well, the oxygen atom in ...”
  Well, the oxygen atom in the water molecule has 2 lone pairs of electrons(electrons that are not shared with other atoms). These electrons push away the bonded pairs of electrons,giving it its "V shape". In the case of carbon dioxide,however,the carbon atom has no lone pairs so there is no repulsion between the bonded pairs and lone pairs.
  For the second part of your question, the electrons are present in a 3D region around the nucleus of an atom. The electrons are not in a fixed position and are constantly moving around in the 3D region.
  Comment on Aysha's post “Well, the oxygen atom in ...”
  (5 votes)
RITESH PAWAR
Posted 4 years ago. Direct link to RITESH PAWAR's post “at 4.02 ,electrons are re...”
at 4.02 ,electrons are revolving around the nucleus , this means they are changing thier positins and changing their bonds . how is this possible if the electrons sometime is not in bond ?
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(3 votes)
Answer
- ScienceLover7
  Posted 3 years ago. Direct link to ScienceLover7's post “Nice question. Electrons...”
  Nice question.
  
  Electrons are not actually revolving around the nucleus, but are present in regions knowns as orbitals. If this is the first time you heard this word, you will probably learn about it in Class 11. Bohr's model of the atom was replaced by a more advanced model called Quantum Model of the Atom. In this model, electrons form bonds by sharing electrons and merging their orbitals. The electrons are continuously moving, but within their given orbital. I am not going into much detail in this answer, but if you want you can check out textbooks of Class 11, or watch some Khan Academy videos.
  
  Hope this helped :)
  
  P.S. Just comment if you want a more detailed answer. I'll try my best.
  Comment on ScienceLover7's post “Nice question. Electrons...”
  (1 vote)
kdhimanjustin87
Posted 4 years ago. Direct link to kdhimanjustin87's post “*Why is an octet so stabl...”
Why is an octet so stable?
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(2 votes)
Answer
- Dishita
  Posted 3 years ago. Direct link to Dishita's post “The no. of valence electr...”
  The no. of valence electrons determine how reactive a substance is.
  An atom always tries to achieve the nearest noble gas electronic configuration (= valence electrons =octet except for atomic no. 1 to 5=duplet)
  
  an Octet (or duplet to those mentioned above) is the most stable electronic configuration of atoms as all orbitals will be full and don't have to gain,lose or share electrons.
  note: the max. no. of electrons in the outer shell is 8
  
  If you're asking why 8 valence electrons and not 6 or 20 or any other no.,
  pardon I do not have the answer to that....yet
  Button navigates to signup page
  (2 votes)
neevkar
Posted a year ago. Direct link to neevkar's post “in the H2O lewis structur...”
in the H2O lewis structure, wont the hydrogen atoms have a dash between them too? as they share an electron with each other
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(1 vote)
Answer
- kaede
  Posted a year ago. Direct link to kaede's post “Not really. As you can se...”
  Not really. As you can see at
  4:24
  , hydrogen is not sharing electrons with each other, it is sharing electrons with oxygen. Which is why the formula of water is H2O, that is 1 atom of oxygen shares electrons with 2 atoms of hydrogen
  Button navigates to signup page
  (2 votes)
DSP
Posted 2 years ago. Direct link to DSP's post “why cant H2O form ionic b...”
why cant H2O form ionic bond
Button navigates to signup pageComment on DSP's post “why cant H2O form ionic b...”
(1 vote)
Answer
Somesh Sahu
Posted 3 years ago. Direct link to Somesh Sahu's post “Are there any exceptions ...”
Are there any exceptions in covalent bond ?
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(1 vote)
Answer
Somesh Sahu
Posted 3 years ago. Direct link to Somesh Sahu's post “The total number of elect...”
The total number of electrons an electron shell can hold is determined by the formula 2n² and it goes by the order 2, 8, 18, 32 electrons and so on. So why do we say that 8 electrons is a stable valence electron number ?
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(1 vote)
Answer
- Nolan Ryzen Terrence
  Posted 2 years ago. Direct link to Nolan Ryzen Terrence's post “@ *Somesh Sahu* do you kn...”
  @ Somesh Sahu do you know that electron shells have subshells?
  It is because of these subshells we have M and N shells able to hold 18 and 32 electrons. Given that there are subshells,8 is the stable valence electron after the subshells are occupied.
  Button navigates to signup page
  (1 vote)
Laasyan
Posted 5 months ago. Direct link to Laasyan's post “how does the shape of a b...”
how does the shape of a bond depend on its electrons. Like what does pyramid, triangular...shaped bonds mean
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(1 vote)
Answer

Class 10 Chemistry (India)

Course: Class 10 Chemistry (India) > Unit 4

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