• Number Of Electrons In Nitrogen-16
• Number Of Electrons In Nitrogen 14
• Number Of Electrons In Nitrogen-14
• What Is The Number Of Electrons In Nitrogen
• Number Of Electrons In Nitrogen 15

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.

Nitrogen is the seventh element with a total of 7 electrons. In writing the electron configuration for nitrogen the first two electrons will go in the 1s orbital. Since 1s can only hold two electrons the next 2 electrons for N goes in the 2s orbital. The remaining three electrons will go in the 2p orbital. In this molecule, oxygen has 2 lone pairs whereas, nitrogen has 1 lone pair. Therefore, a total number of 3 lone pairs of electrons are present. Answer verified by Toppr.

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.

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.

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 N_2. 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.

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

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

Oxides of Nitrogen

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. 8^th 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, N₂O_3, N₂O_4, 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

Quantum Numbers: H to Ne

There are four quantum numbers: n, ℓ, m_ℓ, and m_s. Each one is a particular factor in an equation describing a property of the electron. At this introductory level, the equations are not needed. The value of each quantum number is assigned to each electron in an atom by a 'building up' process. Niels Bohr called this process the 'Aufbau' principle: aufbau means 'building up.'

n is ALWAYS the starting point for building up a series of quantum numbers. Each quantum number is then assigned according to a set of rules, each of which took years of study to finally determine. The rules ARE NOT just any old arbitrary ones; they have been determined from a study of nature. Remember the rules:

(1) n = 1, 2, 3, and so on.
(2) ℓ = 0, 1, 2, . . . , n - 1
(3) m_ℓ starts at negative ℓ, runs by whole numbers to zero and then goes to positive ℓ.
(4) after the n, ℓ and m_ℓ to be used have been determined, assign the m_s value +½ to one electron, then assign the m_s value of -½ to the next electron, while using the same n, ℓ and m values.

Also, keep in mind that we use only one n, ℓ, m_ℓ, and m_s value each to make a set of four quantum numbers for each electron. It is this set of four quantum numbers that uniquely identifies each electron.

Last point: the last column in each table below is called 'Orbital Name.' As you are reading this tutorial, you may not yet know what an orbital is. That's OK, but please understand the concept called 'orbital' is an important one. Here's a real simple description that ignores lots of details: each orbital is a region of space around the nucleus which contains a MAXIMUM of two electrons. Realize that it's more complex than that, but the above description is good enough for now. I hope!!

Hydrogen - one electron

First Electron

n = 1
ℓ = 0
m_ℓ = 0

In each case, note that we start with the smallest value of n, ℓ, or m_ℓ possible. Make sure you look over the rules to see how each value was arrived at. ℓ starts at zero and goes to n - 1, which is zero since we get 1 - 1 = 0, when using n = 1. When ℓ = 0, there is only one possible choice for m_ℓ, which must be zero.

m_s = +½

This completes the four quantum numbers for the single electron possessed by hydrogen. I shall build up a table like this:

Helium - two electrons

First Electron

n = 1
ℓ = 0
m_ℓ = 0
m_s = +½

The first electron in helium has exactly the same four quantum number of the first electron in hydrogen. However, helium has TWO electrons. So we 'build up' from the previous electrons by adding one more.

Second Electron

n = 1
ℓ = 0
m_ℓ = 0
m_s = -½

Notice the same n, ℓ, and m_ℓ values, but m_s has shifted from positive ½ to negative ½. This was the problem Pauli saw in 1925. Three quantum numbers was insufficient to UNIQUELY identify each electron, but a fourth one (the one called m_s) did the trick.

Lithium - three electrons

The first two electrons quantum numbers' are EXACTLY the same as the two in helium:

1, 0, 0, +½ and 1, 0, 0, -½

Third Electron: here's where we 'build up' by adding one more electron.

However, we are now presented with a problem. All the values with n = 1 have been used up, but we have only accounted for two of lithium's three electrons. What to do about the third?

Answer: start with the NEXT n value; n = 2. However, there is a problem with ℓ; do we use ℓ = 0 or ℓ = 1, since both are possible with n = 2?

Answer: start with the lowest value first, so that means using ℓ = 0. (Don't worry, we will use ℓ = 1 soon enough.)

Figuring out m_ℓ should be easy; when ℓ = 0, m_ℓ can only equal 0. So n, ℓ, m_ℓ for the third electron is 2, 0, 0. I'll add in m_s in the table below.

Beryllium - four electrons

In the building up process, we go one electron at a time. Therefore, we will use the three from lithium and add one more.

Fourth Electron

n = 2
ℓ = 0
m_ℓ = 0
m_s = -½

Number Of Electrons In Nitrogen-16

Notice the same n, ℓ, and m values as the third electron, but m_s for the fourth electron has shifted from positive ½ to negative ½.

Pretty easy, eh? It stays easy, if you follow the rules. With beryllium, we have exhausted the possibilities for the n = 2; ℓ = 0 combination. However, when n = 2, ℓ can take on another value, namely ℓ = 1. This has consequences for the m_ℓ value as well and, after we finish, there will be six electrons that have a combination of n = 2 and ℓ = 1.

Here's the rule for m_ℓ again: start at negative ℓ, run by whole numbers to zero and then go to positive ℓ. Since ℓ = 1, we start with -1, go to zero and end up at +1. This gives us three values for m_ℓ when ℓ = 1. Hopefully you can see that, since m_s takes on +½ and -½, we will wind up with six sets of quantum numbers.

Warning: there's going to be a new rule introduced after boron. So prepare yourself because, just as you thought it was getting easy, there gets added some new stuff. By the way, us mean old teachers didn't make all this stuff up to torture poor chemistry students. Nature really does do what I will explain below. Here's boron:

Boron - five electrons

Following the usual pattern, I've repeated the previous four electrons. As we go on to the ℓ = 1 values, keep in mind that we will start with the lowest value of m_ℓ, namely negative one.

Eventually, I will wind up with three orbital names. 2p_x is just the first, x meaning the x-axis. Next will be 2p_y, for the y-axis and the last name used will be 2p_z, for the z-axis. These three orbitals are oriented at 90° to each other.

Hund's Rule (named for Fredrich Hund) is the name of the new rule. This rule concerns the relationship between the ℓ and m_ℓ quantum numbers. When ℓ = 0, m_ℓ can only equal zero and Hund's Rule does not show up. However, now that we have reached ℓ = 1, m_ℓ can take on multiple values. Hund's Rule concerns the order in which we assign the ℓ and m_ℓ values.

By the way, I'm going to avoid a technical statement of Hund's Rule for the moment. I'll discuss how it works first.

Hund's Rule means that we will use each possible ℓ, m_ℓ combination ONCE before going back and using it a second time. Here are the three possible ℓ, m_ℓ combos when ℓ = 1:

For boron, we have used the ℓ, m_ℓ combination of 1, -1. The key is to see that Hund's Rule requires we go on to the NEXT ℓ, m_ℓ combination for the next element: carbon.

Carbon - six electrons

Following the usual pattern, I've repeated the previous five electrons. As we continue on with the ℓ = 1 values, keep in mind that Hund's Rule will affect how we assign the next m_ℓ value.

Nitrogen - seven electrons

Number Of Electrons In Nitrogen 14

Since we still have not first used all possible ℓ, m_ℓ values ONCE, we go on to the next ℓ, m_ℓ combination.

2p_x, 2p_y and 2p_z are three different orbitals, each one capable of holding two electrons. Notice how, in nitrogen, each of the three orbitals is filled up HALF-WAY (that is, with one electron) before we go back and fill up each orbital with the second electron.

This 'half-filled orbital' has definite chemical consequences. Remember it well. Also, using 2p_x first, then going to y and then z is purely convention. The x, y, z order is not of consequence in the above examples. However keep in mind the using each letter ONCE first being using it for the second electron is important.

Oxygen - eight electrons

Number Of Electrons In Nitrogen-14

Now that we have used each ℓ, m_ℓ combination once, we proceed to go back and use each combo the second time. For oxygen to neon, I've marked which electron is the one added.

Fluorine - nine electrons

Neon - ten electrons

What Is The Number Of Electrons In Nitrogen

Number Of Electrons In Nitrogen 15

We have now completed all possible values for n = 1 AND n = 2. Starting with element 11, sodium, we will proceed on to n = 3. When we finish, we will have used ℓ = 0, ℓ = 1 (and applied Hund's Rule again) and then, before going on to ℓ = 3, we will hit another interesting twist that nature has handed us. We will wind up going on to n = 4 and then coming back to finish n = 3. It will be fun!