Crisscross Elements 

King Wen order

I Ching hexagrams
01 ䷀ 02 ䷁ 03 ䷂ 04 ䷃ 05 ䷄ 06 ䷅ 07 ䷆ 08 ䷇ 09 ䷈ 10 ䷉ 11 ䷊ 12 ䷋ 13 ䷌ 14 ䷍ 15 ䷎ 16 ䷏ 17 ䷐ 18 ䷑ 19 ䷒ 20 ䷓ 21 ䷔ 22 ䷕ 23 ䷖ 24 ䷗ 25 ䷘ 26 ䷙ 27 ䷚ 28 ䷛ 29 ䷜ 30 ䷝ 31 ䷞ 32 ䷟ 33 ䷠ 34 ䷡ 35 ䷢ 36 ䷣ 37 ䷤ 38 ䷥ 39 ䷦ 40 ䷧ 41 ䷨ 42 ䷩ 43 ䷪ 44 ䷫ 45 ䷬ 46 ䷭ 47 ䷮ 48 ䷯ 49 ䷰ 50 ䷱ 51 ䷲ 52 ䷳ 53 ䷴ 54 ䷵ 55 ䷶ 56 ䷷ 57 ䷸ 58 ䷹ 59 ䷺ 60 ䷻ 61 ䷼ 62 ䷽ 63 ䷾ 64 ䷿

26	Fe	Iron	55.847
27	Co	Cobalt	58.9332
28	Ni	Nickel	58.70
29	Cu	Copper	63.546
30	Zn	Zinc	65.38
31	Ga	Gallium	69.72
32	Ge	Germanium	72.59
33	As	Arsenic	74.9216
34	Se	Selenium	78.96
35	Br	Bromine	79.904
36	Kr	Krypton	83.80
37	Rb	Rubidium	85.4678
38	Sr	Strontium	87.62
39	Y	Yttrium	88.9059
40	Zr	Zirconium	91.22
41	Nb	Niobium	92.9064
42	Mo	Molybdenum	95.94
43	Tc	Technetium	(98)
44	Ru	Ruthenium	101.07
45	Rh	Rhodium	102.9055
46	Pd	Palladium	106.4
47	Ag	Silver	107.868
48	Cd	Cadmium	112.41
49	In	Indium	114.82
50	Sn	Tin	118.69
51	Sb	Antimony	121.75
52	Te	Tellurium	127.60
53	I	Iodine	126.9045
54	Xe	Xenon	131.30
55	Cs	Cesium	132.9054
56	Ba	Barium	137.33
57	La	Lanthanum	138.9055
58	Ce	Cerium	140.12
59	Pr	Praseodymium	140.9077
60	Nd	Neodymium	144.24
61	Pm	Promethium	(145)
62	Sm	Samarium	150.4
63	Eu	Europium	151.96
64	Gd	Gadolinium	157.25

Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element.

Barium spectre visible

Barium
Pronunciation	/ˈbɛəriəm/ ​(BAIR-ee-əm)
Appearance	silvery gray; with a pale yellow tint
Standard atomic weight Ar, std(Ba)	137.327(7)
Barium in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Sr ↑ Ba ↓ Ra caesium ← barium → lanthanum
Atomic number (Z)	56
Group	group 2 (alkaline earth metals)
Period	period 6
Block	s-block
Element category	Alkaline earth metal
Electron configuration	[Xe] 6s2
Electrons per shell	2, 8, 18, 18, 8, 2
Physical properties
Phase at STP	solid
Melting point	1000 K ​(727 °C, ​1341 °F)
Boiling point	2118 K ​(1845 °C, ​3353 °F)
Density (near r.t.)	3.51 g/cm3
when liquid (at m.p.)	3.338 g/cm3
Heat of fusion	7.12 kJ/mol
Heat of vaporization	142 kJ/mol
Molar heat capacity	28.07 J/(mol·K)
Vapour pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 911 1038 1185 1388 1686 2170
Atomic properties
Oxidation states	+1, +2 (a strongly basic oxide)
Electronegativity	Pauling scale: 0.89
Ionization energies	1st: 502.9 kJ/mol 2nd: 965.2 kJ/mol 3rd: 3600 kJ/mol
Atomic radius	empirical: 222 pm
Covalent radius	215±11 pm
Van der Waals radius	268 pm
Spectral lines of barium
Other properties
Natural occurrence	primordial
Crystal structure	​body-centred cubic (bcc)
Speed of sound thin rod	1620 m/s (at 20 °C)
Thermal expansion	20.6 µm/(m·K) (at 25 °C)
Thermal conductivity	18.4 W/(m·K)
Electrical resistivity	332 nΩ·m (at 20 °C)
Magnetic ordering	paramagnetic[3]
Magnetic susceptibility	+20.6·10−6 cm3/mol[4]
Young's modulus	13 GPa
Shear modulus	4.9 GPa
Bulk modulus	9.6 GPa
Mohs hardness	1.25
CAS Number	7440-39-3
History
Discovery	Carl Wilhelm Scheele (1772)
First isolation	Humphry Davy (1808)
Main isotopes of barium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 130Ba 0.11% (0.5–2.7)×1021 y εε 130Xe 132Ba 0.10% stable 133Ba syn 10.51 y ε 133Cs 134Ba 2.42% stable 135Ba 6.59% stable 136Ba 7.85% stable 137Ba 11.23% stable 138Ba 71.70% stable

Periodic Table with Element Names and Electronegativity

This periodic table chart lists elements by name in alphabetical order including the element symbol, atomic number, and Pauling electronegativity value

Element Name	Symbol	Atomic Number	Electronegativity (χ)
Actinium	Ac	89	1.1
Aluminum	Al	13	1.61
Americium	Am	95	1.3
Antimony	Sb	51	2.05
Argon	Ar	18
Arsenic	As	33	2.18
Astatine	At	85	2.2
Barium	Ba	56	0.89
Berkelium	Bk	97	1.3
Beryllium	Be	4	1.57
Bismuth	Bi	83	2.02
Bohrium	Bh	107
Boron	B	5	2.04
Bromine	Br	35	2.96
Cadmium	Cd	48	1.69
Calcium	Ca	20	1
Californium	Cf	98	1.3
Carbon	C	6	2.55
Cerium	Ce	58	1.12
Cesium	Cs	55	0.79
Chlorine	Cl	17	3.16
Chromium	Cr	24	1.66
Cobalt	Co	27	1.88
Copper	Cu	29	1.9
Curium	Cm	96	1.3
Darmstadtium	Ds	110
Dubnium	Db	105
Dysprosium	Dy	66	1.22
Einsteinium	Es	99	1.3
Erbium	Er	68	1.24
Europium	Eu	63
Fermium	Fm	100	1.3
Fluorine	F	9	3.98
Francium	Fr	87	0.7
Gadolinium	Gd	64	1.2
Gallium	Ga	31	1.81
Germanium	Ge	32	2.01
Gold	Au	79	2.54
Hafnium	Hf	72	1.3
Hassium	Hs	108
Helium	He	2
Holmium	Ho	67	1.23
Hydrogen	H	1	2.2
Indium	In	49	1.78
Iodine	I	53	2.66
Iridium	Ir	77	2.2
Iron	Fe	26	1.83
Krypton	Kr	36	3
Lanthanum	La	57	1.1
Lawrencium	Lr	103
Lead	Pb	82	2.33
Lithium	Li	3	0.98
Lutetium	Lu	71	1.27
Magnesium	Mg	12	1.31
Manganese	Mn	25	1.55
Meitnerium	Mt	109
Mendelevium	Md	101	1.3
Mercury	Hg	80	2
Molybdenum	Mo	42	2.16
Neodymium	Nd	60	1.14
Neon	Ne	10
Neptunium	Np	93	1.36
Nickel	Ni	28	1.91
Niobium	Nb	41	1.6
Nitrogen	N	7	3.04
Nobelium	No	102	1.3
Oganesson	Uuo	118
Osmium	Os	76	2.2
Oxygen	O	8	3.44
Palladium	Pd	46	2.2
Phosphorus	P	15	2.19
Platinum	Pt	78	2.28
Plutonium	Pu	94	1.28
Polonium	Po	84	2
Potassium	K	19	0.82
Praseodymium	Pr	59	1.13
Promethium	Pm	61
Protactinium	Pa	91	1.5
Radium	Ra	88	0.9
Radon	Rn	86
Rhenium	Re	75	1.9
Rhodium	Rh	45	2.28
Roentgenium	Rg	111
Rubidium	Rb	37	0.82
Ruthenium	Ru	44	2.2
Rutherfordium	Rf	104
Samarium	Sm	62	1.17
Scandium	Sc	21	1.36
Seaborgium	Sg	106
Selenium	Se	34	2.55
Silicon	Si	14	1.9
Silver	Ag	47	1.93
Sodium	Na	11	0.93
Strontium	Sr	38	0.95
Sulfur	S	16	2.58
Tantalum	Ta	73	1.5
Technetium	Tc	43	1.9
Tellurium	Te	52	2.1
Terbium	Tb	65
Thallium	Tl	81	1.62
Thorium	Th	90	1.3
Thulium	Tm	69	1.25
Tin	Sn	50	1.96
Titanium	Ti	22	1.54
Tungsten	W	74	2.36
Ununbium	Uub	112
Ununhexium	Uuh	116
Ununpentium	Uup	115
Ununquadium	Uuq	114
Ununseptium	Uus	117
Ununtrium	Uut	113
Uranium	U	92	1.38
Vanadium	V	23	1.63
Xenon	Xe	54	2.6
Ytterbium	Yb	70
Yttrium	Y	39	1.22
Zinc	Zn	30	1.65
Zirconium	Zr	40	1.33