N Valence Electrons

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  1. N # Of Valence Electrons
  2. N Valence Electrons Number

Valence Electrons. The electrons in the outermost shell are the valence electrons the electrons on an atom that can be gained or lost in a chemical reaction. Since filled d or f subshells are seldom disturbed in a chemical reaction, we can define valence electrons as follows: The electrons on an atom that are not present in the previous rare gas, ignoring filled d or f subshells. Valence: The electrons in the outermost shell, or valence shell, are known as valence electrons. These valence electrons are responsible for the chemical properties of the chemical elements. It is these electrons which participate in chemical reactions with other elements. The number of Valence electrons is the number of electrons found on the outermost electron shell of the atom. Nitrogen originally has 7 electrons, and so the N3- ion has 3 extra, giving it 10. The outermost orbital has a capacity of eight electrons.The electronic configuration of nitrogen is 1s2 2s2 2p3. Thus nitrogen has half-filled p orbital, which is comparatively more stable. Thus the p orbital is the outermost orbital. To achieve a stable gas configuration, nitrogen needs to have a fulfilled p orbital. How many valence electrons does N2O5 have? In the gas phase, the oxide N2O5 has a structure with an N-O-N core,and each N bonds to two additional O atoms. In contrast, in the solid phase the stable form is an ionic solid, (NO2+)(NO3- ).

Lewis structure of NO3- ion is drawn step by step in this tutorial. Total valence electrons of nitrogen and oxygen atoms and negative charge are considered to draw the NO3- lewis structure. You will every fact of drawing lewis structures from this tutorial which will help you to draw more lewis structures in the future.


Lewis Structure of nitrite ion


Now, we are going to learn, how to draw this lewis structure of NO3-Cleanmymac x activation key for mac. ion.


Steps of drawing NO3- lewis structure

Following steps are required to draw NO3- lewis structure and they are explained in detail in this tutorial.


  1. Find total number of electrons of the valance shells of nitrogen and oxygen atoms and including charge of the anion
  2. Total electrons pairs in valence shells
  3. Center atom selection from nitrogen and oxygen atom
  4. Put lone pairs on atoms
  5. Stability of lewis structure - Check the stability and minimize charges on atoms by converting lone pairs to bonds.

Drawing correct lewis structure is important to draw resonance structures. In another tutorial, we learn how to draw resonance structures of nitrate ion.


Total number of electrons of the valance shells of nitrogen and oxygen atoms and charge of the anion

There are one nitrogen atom and three oxygen atoms in the nitrate ion. Also there is a -1 charge on the nitrate ion.

Nitrogen and oxygen are located at VA and VIA groups respectively in the periodic table. So nitrogen has five electrons in its valence shell. In oxygen atom, there are six electrons in its valence shell.


  • Total valence electrons given by nitrogen atom = 5

There are three oxygen atoms in NO3-, Therefore

  • Total valence electrons given by oxygen atoms = 6 *3 = 18

Due to -1 charge, another electrons is added

  • Due to -1 charge, received electrons to valence electrons= 1

  • Total valence electrons = 5 + 18 + 1 = 24

Total valence electrons pairs

Total valance electrons pairs = σ bonds + π bonds + lone pairs at valence shells

Total electron pairs are determined by dividing the number total valence electrons by two. For, NO2-, there are 24 valence electrons, so total pairs of electrons are 12.


Center atom of NO2-

To be the center atom, ability of having greater valance is important. Nitrogen can show valence,5. But, oxygen's maximum valence is 2. Therefore nitrogen has the more chance to be the center atom (See the figure). So, now we can build a sketch of NO3- ion.


Sketch of NO2- ion


Lone pairs on atoms

There are already three N-O bonds in the sketch. Therefore only nine valence electrons pairs are remaining to draw the rest of ion.

Start to mark those nine valence electrons pairs on outside atoms (oxygen atoms) as lone pairs. One oxygen atom will take three lone pairs following the octal rule (oxygen and nitrogen atoms cannot keep more than eight electrons in their valence shells). All nine valence electrons pairs (9) are spent when lone pairs are marked on oxygen atoms.

Therefore, there is no ine valence electrons pairs to mark on nitrogen atom.


Check the stability of drawn NO2- ion and minimize charges on atoms by converting lone pairs to bonds

Check charges on atoms and mark them as below. Charges are important to decide the lewis structure of the ion.


The drawn structure for NO3- is not a stable structure because oxygen atoms and nitrogen atoms have charges. When a molecule or ion has so many charges on atoms, that structure is not stable.


Now, we should try to minimize charges by converting lone pair or pairs which exist on oxygen atoms to bonds. So we convert one lone pair of one oxygen atom as a N-O bond.


Now there is a double bond between nitrogen and one oxygen atom. There are also two single bonds (N-O) with nitrogen atom and other oxygen atoms.


In new structure, charges of atoms are reduced. Now there is no any charge on one oxygen atom. Also, charge of nitrogen atom is reduced from +2 to +1. Now you understand this structure of NO3- is more stable than previous structure due to less charges on atoms.


But, We cannot convert more lone pairs of other oxygen atom to make a bond with nitrogen atom because nitrogen cannot keep more than eight electrons in its last valence shell.



Questions


How many lone pairs are around the nitrogen atom in nitrate ion?

No electrons pairs exist on nitrogen atom. But, on nitrogen atom, there is a +1 charge. Around the nitrogen atom, there are two single bonds and double bond.


Related tutorials

NO2 lewis structureN2O lewis structure, resonance structures N2O5 resonance structuresResonance structures examples Nitrogen dioxide acidity


Nitrogen is present in almost all proteins and plays important roles in both biochemical applications and industrial applications. Nitrogen forms strong bonds because of its ability to form a triple bond with its self, and other elements. Thus, there is a lot of energy in the compounds of nitrogen. Before 100 years ago, little was known about nitrogen. Now, nitrogen is commonly used to preserve food, and as a fertilizer.

Introduction

Nitrogen is found to have either 3 or 5 valence electrons and lies at the top of Group 15 on the periodic table. It can have either 3 or 5 valence electrons because it can bond in the outer 2p and 2s orbitals. Molecular nitrogen ((N_2)) is not reactive at standard temperature and pressure and is a colorless and odorless gas.

Nitrogen is a non-metal element that occurs most abundantly in the atmosphere, nitrogen gas (N2) comprises 78.1% of the volume of the Earth’s air. It only appears in 0.002% of the earth's crust by mass. Compounds of nitrogen are found in foods, explosives, poisons, and fertilizers. Nitrogen makes up DNA in the form of nitrogenous bases as well as in neurotransmitters. It is one of the largest industrial gases, and is produced commercially as a gas and a liquid.

Table 1: General Properties of Nitrogen
Name and SymbolNitrogen, N
Categorynon-metal
Atomic Weight14.0067
Group15
Electron Configuration1s2 2s2 2p3
Valence Electrons2, 5
PhaseGas

History

Nitrogen, which makes up about 78% of our atmosphere, is a colorless, odorless, tasteless and chemically unreactive gas at room temperature. It is named from the Greek nitron + genes for soda forming. For many years during the 1500's and 1600's scientists hinted that there was another gas in the atmosphere besides carbon dioxide and oxygen. It was not until the 1700's that scientists could prove there was in fact another gas that took up mass in the atmosphere of the Earth.

Discovered in 1772 by Daniel Rutherford (and independently by others such as Priestly and Cavendish) who was able to remove oxygen and carbon dioxide from a contained tube full of air. He showed that there was residual gas that did not support combustion like oxygen or carbon dioxide. While his experiment was the one that proved that nitrogen existed, other experiments were also going in London where they called the substance 'burnt' or 'dephlogisticated air'.

Nitrogen is the fourth most abundant element in humans and it is more abundant in the known universe than carbon or silicon. Most commercially produced nitrogen gas is recovered from liquefied air. Of that amount, the majority is used to manufacture ammonia ((NH_3)) via the Haber process. Much is also converted to nitric acid ((HNO_3)).

Isotopes

Nitrogen has two naturally occurring isotopes, nitrogen-14 and nitrogen-15, which can be separated with chemical exchanges or thermal diffusion. Nitrogen also has isotopes with 12, 13, 16, 17 masses, but they are radioactive.

  • Nitrogen 14 is the most abundant form of nitrogen and makes up more than 99% of all nitrogen found on Earth. It is a stable compound and is non-radioactive. Nitrogen-14 has the most practical uses, and is found in agricultural practices, food preservation, biochemicals, and biomedical research. Nitrogen-14 is found in abundance in the atmosphere and among many living organisms. It has 5 valence electrons and is not a good electrical conductor.
  • Nitrogen-15 is the other stable form of nitrogen. It is often used in medical research and preservation. The element is non-radioactive and therefore can also be sometimes used in agricultural practices. Nitrogen-15 is also used in brain research, specifically nuclear magnetic resonance spectroscopy (NMR), because unlike nitrogen-14 (nuclear spin of 1), it has a nuclear spin of 1/2 which has benefits when it comes to observing MRI research and NMR observations. Lastly, nitrogen-15 can be used as label or in some proteins in biology. Scientists mainly use this compound for research purposes and have not yet seen its full potential for uses in brain research.

Compounds

The two most common compounds of nitrogen are Potassium Nitrate (KNO3) and Sodium Nitrate (NaNO3). These two compounds are formed by decomposing organic matter that has potassium or sodium present and are often found in fertilizers and byproducts of industrial waste. Most nitrogen compounds have a positive Gibbs free energy (i.e., reactions are not spontaneous).

The dinitrogen molecule ((N_2)) is an 'unusually stable' compound, particularly because nitrogen forms a triple bond with itself. This triple bond is difficult hard to break. For dinitrogen to follow the octet rule, it must have a triple bond. Nitrogen has a total of 5 valence electrons, so doubling that, we would have a total of 10 valence electrons with two nitrogen atoms. The octet requires an atom to have 8 total electrons in order to have a full valence shell, therefore it needs to have a triple bond. The compound is also very inert, since it has a triple bond. Triple bonds are very hard to break, so they keep their full valence shell instead of reacting with other compounds or atoms. Think of it this way, each triple bond is like a rubber band, with three rubber bands, the nitrogen atoms are very attracted to each other.

Valence

Nitrides

Nitrides are compounds of nitrogen with a less electronegative atom; in other words it's a compound with atoms that have a less full valence shell. These compounds form with lithium and Group 2 metals. Nitrides usually has an oxidation state of -3.

[3Mg + N_2 rightarrow Mg_3N_2 label{1}]

When mixed with water, nitrogen will form ammonia and, this nitride ion acts as a very strong base.

[N + 3H_2O_{(l)} rightarrow NH_3 + 3OH^-_{(aq)} label{2}]

When nitrogen forms with other compounds it primarily forms covalent bonds. These are normally done with other metals and look like: MN, M3N, and M4N. These compounds are typically hard, inert, and have high melting points because nitrogen's ability to form triple covalent bonds.

Ammonium Ions

Nitrogen goes through fixation by reaction with hydrogen gas over a catalyst. This process is used to produce ammonia. As mentioned earlier, this process allows us to use nitrogen as a fertilizer because it breaks down the strong triple bond held by N2. The famous Haber-Bosch process for synthesis of ammonia looks like this:

[N_2 + 3H_2 rightarrow 2NH_3 label{3}]

Ammonia is a base and is also used in typical acid-base reactions.

Electrons

[2NH_{3(aq)} + H_2SO_4 rightarrow (NH_4)_2SO_{4(aq)} label{4}]

Nitride ions are very strong bases, especially in aqueous solutions.

N # Of Valence Electrons

Oxides of Nitrogen

N Valence Electrons Number

Nitrides use a variety of different oxidation numbers from +1 to +5 to for oxide compounds. Almost all the oxides that form are gasses, and exist at 25 degrees Celsius. Oxides of nitrogen are acidic and easily attach protons.

[N_2O_5 + H_2O rightarrow 2HNO_{3 (aq)} label{5}]

The oxides play a large role in living organisms. They can be useful, yet dangerous.

  • Dinitrogen monoxide (N2O) is a anesthetic used at the dentist as a laughing gas.
  • Nitrogen dioxide (NO2) is harmful. It binds to hemoglobin molecules not allowing the molecule to release oxygen throughout the body. It is released from cars and is very harmful.
  • Nitrate (NO3-) is a polyatomic ion.
  • The more unstable nitrogen oxides allow for space travel.

Hydrides

Hydrides of nitrogen include ammonia (NH3) and hyrdrazine (N2H4).

  • In aqueous solution, ammonia forms the ammonium ion which we described above and it has special amphiprotic properties.
  • Hyrdrazine is commonly used as rocket fuel

Applications of Nitrogen

  • Nitrogen provides a blanketing for our atmosphere for the production of chemicals and electronic compartments.
  • Nitrogen is used as fertilizer in agriculture to promote growth.
  • Pressurized gas for oil.
  • Refrigerant (such as freezing food fast)
  • Explosives.
  • Metals treatment/protectant via exposure to nitrogen instead of oxygen

References

  1. Petrucci, Ralph H, William Harwood, and F. Herring. General Chemistry: Principles and Modern Applications. 8th Ed. New Jersey: Pearson Education Inc, 2001.
  2. Sadava, David et al. LIFE: The Science of Biology. Eighth Edition. Sinauer Associate.
  3. Thomas, Jacob. Nitrogen and its Applications to Modern Future. San Diego State University Press: 2007.

Problems

  • Complete and balance the following equations

N2+ ___H2→ ___NH_

H2N2O2 → ?

2NH3 + CO2 → ?

__Mg + N2 → Mg_N_

N2H5 + H2O → ?

  • What are the different isotopes of Nitrogen?
  • List the oxiadation states of various nitrogen oxides: N2O, NO, N2O3, N2O4, N2O5
  • List the different elements that Nitrogen will react with to make it basic or acidic..
  • Uses of nitrogen

Answers

  • Complete and balance the following equations

N2+ 3H2→ 2NH3(Haber process)

H2N2O2 → HNO

2NH3 + CO2 → (NH2)2CO + H2O

2Mg + 3N2 → Mg3N2

N2H5 + H2O → N2+ H+ + H2O

  • What are the different isotopes of Nitrogen?

Stable forms include nitrogen-14 and nitrogen-15

  • List the oxidation states of various nitrogen oxides: +1, +2, +3, +4, +5 respectively
  • List the different elements that Nitrogen will react with to make it basic or acidic :Nitride ion is a strong base when reacted with water, Ammonia is generally a weak acid
  • Uses of nitrogen include anesthetic, Refrigerant, metal protector