Ar Atomic Mass

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  1. Relative Atomic Mass Ar
  2. Element Ar
  3. Ar Atomic Mass
  4. Ar Atomic Mass In Kg
  5. Ar Relative Atomic Mass

Element Argon - Ar

  1. Element Argon (Ar), Group 18, Atomic Number 18, p-block, Mass 39.95. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images.
  2. Name: Argon Symbol: Ar Atomic Number: 18 Atomic Mass: 39.948 amu Melting Point:-189.3 °C (83.85 K, -308.74 °F) Boiling Point:-186.0 °C (87.15 K, -302.8 °F) Number of Protons/Electrons: 18 Number of Neutrons: 22 Classification: Noble Gas Crystal Structure: Cubic Density @ 293 K: 1.784 g/cm 3 Color: Colorless Gas Atomic Structure.
  3. The atomic mass of aluminum is 26.98 amu. Aluminum is one of the lightest elements, making it ideal for construction, transportation and other commercial uses. Aluminum is a very common element, third in abundance only to silicon and oxygen.
  4. Argon (18 Ar) has 26 known isotopes, from 29 Ar to 54 Ar and 1 isomer (32m Ar), of which three are stable (36 Ar, 38 Ar, and 40 Ar). On the Earth, 40 Ar makes up 99.6% of natural argon. The longest-lived radioactive isotopes are 39 Ar with a half-life of 269 years, 42 Ar with a half-life of 32.9 years, and 37 Ar with a half-life of 35.04 days.

Download Citation Atomic Mass and Nuclear Binding Energy for Ar-51 (Argon) This document is part of the Supplement containing the complete sets of data of Subvolume A ‘Nuclei with Z = 1 - 54.

Comprehensive data on the chemical element Argon is provided on this page; including scores of properties, element names in many languages, most known nuclides of Argon. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

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Overview of Argon

  • Atomic Number: 18
  • Group: 18
  • Period: 3
  • Series: Noble Gasses

Argon's Name in Other Languages

  • Latin: Argon
  • Czech: Argon
  • Croatian: Argon
  • French: Argon
  • German: Argon - r
  • Italian: Argo
  • Norwegian: Argon
  • Portuguese: Argônio
  • Russian: Аргон
  • Spanish: Argón
  • Swedish: Argon

Atomic Structure of Argon

  • Atomic Radius: 0.88Å
  • Atomic Volume: 28.5cm3/mol
  • Covalent Radius: 0.98Å
  • Cross Section (Thermal Neutron Capture)σa/barns: 0.675
  • Crystal Structure: Cubic face centered
  • Electron Configuration:
    1s2 2s2p6 3s2p6
  • Electrons per Energy Level: 2,8,8
    Shell Model
  • Ionic Radius:
  • Filling Orbital: 3p6
  • Number of Electrons (with no charge): 18
  • Number of Neutrons (most common/stable nuclide): 22
  • Number of Protons: 18
  • Oxidation States: 0
  • Valence Electrons: 3s2p6
    Electron Dot Model

Relative Atomic Mass Ar

Chemical Properties of Argon

  • Electrochemical Equivalent:
  • Electron Work Function:
  • Electronegativity: N/A (Pauling); 3.2 (Allrod Rochow)
  • Heat of Fusion: 1.188kJ/mol
  • Incompatibilities:
  • Ionization Potential
    • First: 15.759
    • Second: 27.629
    • Third: 40.74
  • Valence Electron Potential (-eV):

Physical Properties of Argon

  • Atomic Mass Average: 39.948
  • Boiling Point: 87.45K -185.7°C -302.3°F
  • Coefficient of lineal thermal expansion/K-1: N/A
  • Conductivity
    Electrical:
    Thermal: 0.0001772 W/cmK
  • Density: 1.7824g/L @ 273K & 1atm
  • Description:
    Colorless, odorless, tasteless noble gas.
  • Enthalpy of Fusion: 1.18 kJ/mole
  • Enthalpy of Vaporization: 6.43 kJ/mole
  • Flammablity Class:
  • Freezing Point:see melting point
  • Heat of Vaporization: 6.447kJ/mol
  • Melting Point: 83.96K -189.19°C -308.54°F
  • Molar Volume: 24.2 cm3/mole
  • Optical Refractive Index: 1.000281
  • Physical State (at 20°C & 1atm): Gas
  • Specific Heat: 0.52J/gK

Regulatory / Health

  • CAS Number
    • 7440-37-1
  • UN/NA ID and ERG Guide Number
    • UN1006
  • RTECS: CF2300000
  • OSHAPermissible Exposure Limit (PEL)
    • No limits set by OSHA
  • OSHA PEL Vacated 1989
    • No limits set by OSHA
  • NIOSHRecommended Exposure Limit (REL)
    • No limits set by NIOSH
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: trace
    • Bone/p.p.m: nil
    • Liver/p.p.m: nil
    • Muscle/p.p.m: nil
    • Daily Dietary Intake: n/a
    • Total Mass In Avg. 70kg human: n/a

Who / Where / When / How

  • Discoverer: Sir William Ramsey, Lord Baron Rayleigh
  • Discovery Location: Bristol England (Ramsey)/London England (Rayleigh)
  • Discovery Year: 1894
  • Name Origin:
    Greek: Argos (inactive).
  • Abundance of Argon:
    • Earth's Crust/p.p.m.: 1.2
    • Seawater/p.p.m.: 0.45
    • Atmosphere/p.p.m.: 9300
    • Sun (Relative to H=1E12): 1000000
  • Sources of Argon:
    Argon makes up 1% of the air and is isolated by removing nitrogen, oxygen, carbon dioxide and water from air. Argon is constantly being formed from the radioactive decay of K-40 (an isotope of potassium). of radioactive potassium-40. World wide commercial production is around 700,000 tons per year.
  • Uses of Argon:
    Argon is used for lighting. It may also be used to provide an inert atmosphere for certain projects when explosion or other forms of oxidation may pose a problem. Also used in 'Geiger' counters, which measure radiation levels.
  • Additional Notes:

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Element Ar

Ar relative atomic mass

References

A list of reference sources used to compile the data provided on our periodic table of elements can be found on the main periodic table page.

Related Resources

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    Answers many questions regarding the structure of atoms.
  • Molarity, Molality and Normality
    Introduces stoichiometry and explains the differences between molarity, molality and normality.
  • Molar Mass Calculations and Javascript Calculator
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Ar Atomic Mass

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Ar Atomic Mass In Kg

Kenneth Barbalace. Periodic Table of Elements - Argon - Ar. EnvironmentalChemistry.com. 1995 - 2021. Accessed on-line: 4/25/2021
https://EnvironmentalChemistry.com/yogi/periodic/Ar.html
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The atomic mass of an element is the average mass of the atoms of an element measured in atomic mass unit (amu, also known as daltons, D). The atomic mass is a weighted average of all of the isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope. (Atomic mass is also referred to as atomic weight, but the term 'mass' is more accurate.)

For instance, it can be determined experimentally that neon consists of three isotopes: neon-20 (with 10 protons and 10 neutrons in its nucleus) with a mass of 19.992 amu and an abundance of 90.48%, neon-21 (with 10 protons and 11 neutrons) with a mass of 20.994 amu and an abundance of 0.27%, and neon-22 (with 10 protons and 12 neutrons) with a mass of 21.991 amu and an abundance of 9.25%. The average atomic mass of neon is thus:

Ar Relative Atomic Mass

0.9048×19.992 amu=18.09 amu
0.0027×20.994 amu= 0.057 amu
0.0925×21.991 amu= 2.03 amu
20.18 amu

The atomic mass is useful in chemistry when it is paired with the mole concept: the atomic mass of an element, measured in amu, is the same as the mass in grams of one mole of an element. Thus, since the atomic mass of iron is 55.847 amu, one mole of iron atoms would weigh 55.847 grams. The same concept can be extended to ionic compounds and molecules. One formula unit of sodium chloride (NaCl) would weigh 58.44 amu (22.98977 amu for Na + 35.453 amu for Cl), so a mole of sodium chloride would weigh 58.44 grams. One molecule of water (H2O) would weigh 18.02 amu (2×1.00797 amu for H + 15.9994 amu for O), and a mole of water molecules would weigh 18.02 grams.

The original periodic table of the elements published by Dimitri Mendeleev in 1869 arranged the elements that were known at the time in order of increasing atomic weight, since this was prior to the discovery of the nucleus and the interior structure of the atom. The modern periodic table is arranged in order of increasing atomic number instead.