The Atomic Mass Of An Element Is

The elemenents of the periodic table sorted by atomic mass

What Is The Atomic Mass
The Atomic Mass Of An Element Is What

Fundamental properties of atoms including atomic number and atomic mass. The atomic number is the number of protons in an atom, and isotopes have the same atomic number but. Oganesson has the highest atomic number and highest atomic mass of all known elements. The radioactive oganesson atom is very unstable, and since 2005, only five (possibly six) atoms of the isotope oganesson-294 have been detected. The atomic mass of an isotope and the relative isotopic mass refers to a certain specific isotope of an element. Because substances are usually not isotopically pure, it is convenient to use the elemental atomic mass which is the average (mean) atomic mass of an element, weighted by the abundance of the isotopes.

Isotopic atomic species ¶ Note that isotopic atomic species of a given element is uniquely identified by the mass number A, also called atomic mass number, which is the number of nucleons (protons and neutrons) in an atomic nucleus. Explain why the atomic mass of an element is often not in integral number? What are the common product of an acid-base neutralization process? What are the most significant differences of the chemical structure of the DNA and RNA? What is the organic base that replace thymine (T) in the RNA?

click on any element's name for further information on chemical properties, environmental data or health effects.

This list contains the 118 elements of chemistry.

The chemical elements of the periodic chart sorted by:	Atomic Mass	Name chemical element	Symbol	Atomic number
- Name alphabetically	1.0079	Hydrogen	H	1
- Atomic number	4.0026	Helium	He	2
- Symbol	6.941	Lithium	Li	3
- Atomic Mass	9.0122	Beryllium	Be	4
- Electronegativity	10.811	Boron	B	5
- Density	12.0107	Carbon	C	6
- Melting point	14.0067	Nitrogen	N	7
- Boiling point	15.9994	Oxygen	O	8
- Vanderwaals radius	18.9984	Fluorine	F	9
- Year of discovery	20.1797	Neon	Ne	10
- Inventor surname	22.9897	Sodium	Na	11
- Elements in earthcrust	24.305	Magnesium	Mg	12
- Elements in human body	26.9815	Aluminum	Al	13
- Covalenz radius	28.0855	Silicon	Si	14
- Ionization energy	30.9738	Phosphorus	P	15
For chemistry students and teachers: The tabular chart on the right is arranged by Atomic mass (weight). The lightest chemical element is Hydrogen and the heaviest is Hassium. The unity for atomic mass is gram per mol. Please note that the elements do not show their natural relation towards each other as in the Periodic system. There you can find the metals, semi-conductor(s), non-metal(s), inert noble gas(ses), Halogens, Lanthanoides, Actinoids (rare earth elements) and transition metals.	32.065	Sulfur	S	16
	35.453	Chlorine	Cl	17
	39.0983	Potassium	K	19
	39.948	Argon	Ar	18
	40.078	Calcium	Ca	20
	44.9559	Scandium	Sc	21
	47.867	Titanium	Ti	22
	50.9415	Vanadium	V	23
	51.9961	Chromium	Cr	24
	54.938	Manganese	Mn	25
	55.845	Iron	Fe	26
	58.6934	Nickel	Ni	28
	58.9332	Cobalt	Co	27
	63.546	Copper	Cu	29
	65.39	Zinc	Zn	30
	69.723	Gallium	Ga	31
	72.64	Germanium	Ge	32
	74.9216	Arsenic	As	33
	78.96	Selenium	Se	34
79.904	Bromine	Br	35
83.8	Krypton	Kr	36
85.4678	Rubidium	Rb	37
87.62	Strontium	Sr	38
88.9059	Yttrium	Y	39
91.224	Zirconium	Zr	40
92.9064	Niobium	Nb	41
95.94	Molybdenum	Mo	42
98	Technetium	Tc	43
101.07	Ruthenium	Ru	44
102.9055	Rhodium	Rh	45
106.42	Palladium	Pd	46
107.8682	Silver	Ag	47
112.411	Cadmium	Cd	48
114.818	Indium	In	49
118.71	Tin	Sn	50
121.76	Antimony	Sb	51
126.9045	Iodine	I	53
127.6	Tellurium	Te	52
131.293	Xenon	Xe	54
132.9055	Cesium	Cs	55
137.327	Barium	Ba	56
138.9055	Lanthanum	La	57
140.116	Cerium	Ce	58
140.9077	Praseodymium	Pr	59
144.24	Neodymium	Nd	60
145	Promethium	Pm	61
150.36	Samarium	Sm	62
151.964	Europium	Eu	63
157.25	Gadolinium	Gd	64
158.9253	Terbium	Tb	65
162.5	Dysprosium	Dy	66
164.9303	Holmium	Ho	67
167.259	Erbium	Er	68
168.9342	Thulium	Tm	69
173.04	Ytterbium	Yb	70
174.967	Lutetium	Lu	71
178.49	Hafnium	Hf	72
180.9479	Tantalum	Ta	73
183.84	Tungsten	W	74
186.207	Rhenium	Re	75
190.23	Osmium	Os	76
192.217	Iridium	Ir	77
195.078	Platinum	Pt	78
196.9665	Gold	Au	79
200.59	Mercury	Hg	80
204.3833	Thallium	Tl	81
207.2	Lead	Pb	82
208.9804	Bismuth	Bi	83
209	Polonium	Po	84
210	Astatine	At	85
222	Radon	Rn	86
223	Francium	Fr	87
226	Radium	Ra	88
227	Actinium	Ac	89
231.0359	Protactinium	Pa	91
232.0381	Thorium	Th	90
237	Neptunium	Np	93
238.0289	Uranium	U	92
243	Americium	Am	95
244	Plutonium	Pu	94
247	Curium	Cm	96
247	Berkelium	Bk	97
251	Californium	Cf	98
252	Einsteinium	Es	99
257	Fermium	Fm	100
258	Mendelevium	Md	101
259	Nobelium	No	102
261	Rutherfordium	Rf	104
262	Lawrencium	Lr	103
262	Dubnium	Db	105
264	Bohrium	Bh	107
266	Seaborgium	Sg	106
268	Meitnerium	Mt	109
272	Roentgenium	Rg	111
277	Hassium	Hs	108
Darmstadtium	Ds	110
Ununbium	Uub	112
Ununtrium	Uut	113
Ununquadium	Uuq	114
Ununpentium	Uup	115
Ununhexium	Uuh	116
Ununseptium	Uus	117
Ununoctium	Uuo	118

Click here: for a schematic overview of the periodic table of elements in chart form

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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:

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.

What Is The Atomic Mass

The Atomic Mass Of An Element Is What

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.