Tag Archives: nonmetal

Oxygen Facts

Oxygen is the eighth element of the periodic table. These oxygen facts contain chemical and physical data along with general information and history.

Element cell for Oxygen

Oxygen periodic table tile

Basic Oxygen Facts

Name: Oxygen

Atomic Number: 8

Element Symbol: O

Group: 16

Period: 2

Block: p

Element Family: nonmetal

Atomic Mass: [15.999 03; 15.999 77] IUPAC guidelines. For single value, use 15.9994.

Electron Configuration: [He]2s22p(shorthand) or 1s22s22p(full)

Discovery: Carl Wilhelm Scheele in 1773 and Joseph Priestley in 1774. Priestley is often given priority because his work was published first. Both men noticed heating particular oxides released a gas which caused candles to burn brighter. Priestley went a little bit further by placing a mouse in a jar of oxygen. He expected it to survive only a few minutes before suffocating. Instead, the mouse was still alive after an hour in the jar.

Name Origin: French chemist Antoine Lavoisier named the element oxygene from the Greek words oxys meaning “acid” and genes meaning “forming”. At the time, it was believed all acids required oxygen to part of the reaction.

Isotopes:

Natural oxygen is comprised of two stable isotopes: 16O, 17O and 18O. Radioactive isotopes have been produced under laboratory conditions ranging from 12O to 24O.

16O
Oxygen-16 is a stable isotope containing 8 neutrons. 99.757% of natural oxygen is oxygen-16.

17O
Oxygen-17 is a stable isotope containing 9 neutrons. 0.038% of natural oxygen is oxygen-17.

18O
Oxygen-18 is a stable isotope containing 9 neutrons. 0.205% of natural oxygen is oxygen-18.


Liquid Oxygen

Liquid oxygen has a distinctive blue color. Credit: Dr. Warwick Hillier / Australian National University

Physical Data

Density: 0.001308 g/cm3

Melting Point: 54.36 K ​(−218.79 °C, ​−361.82 °F)

Boiling Point: 90.188 K ​(−182.962 °C, ​−297.332 °F)

Triple Point: 54.361 K at ​0.1463 kPa

Critical Point: 154.581 K at 5.043 MPa

State at 20ºC: Gas

Heat of Fusion: 0.444 kJ/mol for O2

Heat of Vaporization: 6.82 kJ/mol for O2

Molar Heat Capacity: 29.378 J/mol·K for O2


Oxygen atom

Electron configuration of an oxygen atom.

Atomic Data

Atomic Radius: 1.52 Å

Covalent Radius: 0.64 Å

Van der Waals Radius:  1.55 Å

Electron Affinity: 140.976 kJ/mol

Electronegativity: (Pauling scale): 3.44

1st Ionization Energy: 1313.942 kJ/mol

2nd Ionization Energy: 3388.671 kJ/mol

3rd Ionization Energy: 5300.47 kJ/mol

4th Ionization Energy: 7469.271 kJ/mol

5th Ionization Energy: 10989.584 kJ/mol

6th Ionization Energy: 13326.526 kJ/mol

7th Ionization Energy: 71330.65 kJ/mol

8th Ionization Energy: 84078.3 kJ/mol

Oxidation States: -2, -1 (common), +2, +1 (uncommon)


Green Aurora in Iceland (Anne Helmenstine)

Green Aurora in Iceland. The green color is caused by the ionization of oxygen in the upper atmosphere. (Anne Helmenstine)

Fun Oxygen Facts

  • Oxygen is a colorless, tasteless and odorless gas, but liquid oxygen has a distinct blue color.
  • Oxygen makes up about 21% of the air you breathe by volume.
  • Nearly half the Earth’s crust is oxygen by mass.
  • Oxygen is the most abundant element in the human body accounting for 65% of your weight.
  • All animals and plants require oxygen to live.
  • Oxygen readily dissolves in water. This property makes life underwater possible.
  • Oxygen gas is used extensively by the steel industry to make steel. It is also used to make hydrogen peroxide and nitric acid. The compound epoxyethane is produced to make the common polymers polyester and PVC (polyvinylchloride)
  • The green waves of color in the auroras is caused by the ionization of oxygen in the upper atmosphere.
  • Oxygen is rarely found alone in nature. Oxygen bonds to itself to form diatomic O2. Ozone is another pure oxygen molecule with formula O3.
  • Ozone is vital to absorb harmful ultraviolet radiation from the Sun in the upper atmosphere. Closer to the ground, however, ozone is considered a pollutant and is hazardous to life.
  • Oxygen was the standard for measuring the atomic weights of other elements until 1961. It was replaced by the mass of carbon-12.

Learn more about elements on the periodic table.

Nitrogen Facts – Element Number 7 or N

Nitrogen is the seventh element of the periodic table. These nitrogen facts contain chemical and physical data along with general information and history.

Element cell for Nitrogen

Nitrogen Periodic Table Tile

Basic Nitrogen Facts

Name: Nitrogen

Atomic Number: 7

Element Symbol: N

Group: 15

Period: 2

Block: p

Element Family: nonmetal

Atomic Mass: [14.006 43; 14.007 28] IUPAC guidelines. For single value, use 14.0067.

Electron Configuration: [He]2s22p(shorthand) or 1s22s22p(full)

Discovery: Daniel Rutherford in 1772
Rutherford’s teacher, Scottish chemist Joseph Black was working on the chemistry of air. When he removed the oxygen by burning phosphorus. He found there was still some gas left over. This mystery was left as an exercise for his student. Rutherford continued by removing the carbon dioxide from the air and showed the remaining gas did not support life or further combustion. He discovered the remaining air was insoluble in water and alkali solutions. He called his air “noxious air”.

Name Origin: Nitrogen’s name comes from the Greek words nitron and genes meaning niter and forming respectively. In 1790, French chemist Jean-Antoine-Claude Chaptal noticed the gas was part of the substance niter (potassium nitrate). French chemist Antoine Lavoisier called the gas azote from the Greek word azotos meaning lifeless. Several countries still use the name Azote for nitrogen in general use.

Isotopes:

Natural nitrogen is comprised of two stable isotopes: N-14 and N-15. Fourteen other isotopes have been produced under laboratory conditions ranging from N-10 to N-25.

14N
Nitrogen-14 is a stable isotope containing 7 neutrons. 99.636% of natural nitrogen is nitrogen-14.

15N
Nitrogen-15 is a stable isotope containing 8 neutrons. 0.364% of natural nitrogen is nitrogen-11.


Liquid Nitrogen (Cory Doctorow)

Liquid Nitrogen being poured from a dewar. Credit: Cory Doctorow

Physical Data

Density: 0.001145 g/cm3

Melting Point: 63.2 K (-210.0 ºC or -346.0 ºF)

Boiling Point: 77.355 K (-195.795 ºC or -320.431 ºF)

Triple Point: 63.151 K at 12.52 kPa

Critical Point: 126.192 K at 3.3958 MPa

State at 20ºC: Gas

Heat of Fusion: 0.72 kJ/mol for N2

Heat of Vaporization: 5.56 kJ/mol for N2

Molar Heat Capacity: 29.124 J/mol·K for N2


Nitrogen atom

Electron configuration of a nitrogen atom.

Atomic Data

Atomic Radius: 1.55 Å

Covalent Radius: 0.71 Å

Van der Waals Radius:  1.55 Å

Electron Affinity: not stable

Electronegativity: (Pauling scale): 3.04

1st Ionization Energy: 1402.328 kJ/mol

2nd Ionization Energy: 2856.092 kJ/mol

3rd Ionization Energy: 4578.156 kJ/mol

4th Ionization Energy: 7475.057 kJ/mol

5th Ionization Energy: 9444.969 kJ/mol

6th Ionization Energy: 53266.835 kJ/mol

7th Ionization Energy: 64360.16 kJ/mol

Oxidation States: +5, +3, -3 (common), +4, +2, +1, -1, -2 (uncommon)


Saturn's Moon Titan

Natural color photograph of Saturn’s largest moon, Titan. Taken by Cassini probe during Saturn flyby in 2005. Credit: NASA/JPL

Fun Nitrogen Facts

  • Nitrogen is a colorless, tasteless and odorless gas.
  • Nitrogen is not found as a single element in nature. It bonds to itself to form the diatomic compound N2.
  • Nitrogen gas makes up 78% of our atmosphere.
  • Approximately 49 million tons of nitrogen are removed from the atmosphere to produce ammonia.
  • Group 15 on the periodic table is also known as the nitrogen family. An older name for the group was pnictogens. Pnictogen is from the Greek word pnikta meaning “to choke”.
  • Nitrogen is used to protect goods from oxygen. The ‘air’ in your potato chip bag is mostly nitrogen.
  • About 3% of your body weight is nitrogen. It is also the fourth most abundant element in the human body after oxygen, carbon and hydrogen.
  • Nitrogen is a key component of amino acids. There is nitrogen in every part of your DNA.
  • Nitrogen gas is relatively inert. Soil bacteria can ‘fix’ nitrogen into forms plants use to grow.
  • Nitrogen is responsible for the vibrant orange-red, blue-green, blue-violet, and deep violet colors of the aurora.
  • Saturn’s moon Titan has a dense atmosphere comprised almost entirely of nitrogen and nitrogen compounds. The yellow-orange haze (see picture)  is caused by hydrocarbon smog suspended in the atmosphere.

Learn more about elements on the periodic table.