Mendeleev's Periodic Table > Sr - Strontium

Sr - Strontium

An alkaline earth metal. Discovered in 1790 by Crawford in Scotland, and obtained as a metal by Davy in 1807 in London. Strontium does not occur as the free element. Strontium is softer than calcium and decomposes water more vigorously. Freshly cut strontium has a silvery appearance, but rapidly turns a yellowish colour with the formation of the oxide. The finely divided metal ignites spontaneously in air. Volatile strontium salts impart an excellent crimson colour to flames, and these salts are used in pyrotechnics.

Atomic number	-	38		Density	g/mL	2	.6
Atomic weight	u	87	.62	Melting point	K	1041
Bonding radius	A	1	.91	Boiling point	K	1650
Atomic radius	A	2	.45	Heat of vaporization	kJ/mol	144
Ionization Potential	V	5	.695	Heat of fusion	kJ/mol	8	.3
Electronegativity	-	0	.95	Specific heat	J/gK	0	.3
The oxide is a strong base.				Crystal are face centered cubic.
Electron config. : [Kr] 5s²

Isotopes of Sr (Strontium):

MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	075 150 nsec EC/ECp,7.020 Rb-75/Kr-74 74.949972	076 8.9 sec EC,6.100 MeV Rb-76 75.941599	077 9.0 sec EC/ECp,6.850 Rb-77/Kr-76 76.937766	078 2.5 min EC,3.762 MeV Rb-78 77.932182
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	079 2.25 min EC,5.318 MeV Rb-79 78.929709	080 106.3 min EC,1.868 MeV Rb-80 79.924527	081 22.3 min EC,3.930 MeV Rb-81 80.923213	082 25.55 da EC,4.469 MeV Rb-82 81.918401
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	083 32.41 hr EC,2.276 MeV Rb-83 82.917555	084 0.56% Stable 83.913426	085 64.84 da EC,1.065 MeV Rb-85 84.912935	085a 67.63 min EC,1.304 MeV Rb-85 84.913192
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	086 9.86% Stable 85.909264	087 7.00% ECStable Rb-87 86.908879	088 82.58% Stable 87.905616	089 50.53 da B-,1.495 MeV Y-89 88.907453
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	090 28.78 yr B-,6.697 MeV Y-90 89.907738	091 9.63 hr B-,2.699 MeV Y-91 90.910199	092 2.71 hr B-,1.911 MeV Y-92 91.910981	093 7.423 min B-,4.137 MeV Y-93 92.914022
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	094 75.3 sec B-,3.511 MeV Y-94 93.915365	095 23.90 sec B-,6.080 MeV Y-95 94.919313	096 1.07 sec B-,5.371 MeV Y-96 95.921649	097 429 msec B-/B-n,7.467 Y-97/Y-96 96.926145
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	098 0.653 sec B-/B-n,5.826 Y-98/Y-97 97.928491	099 0.269 sec B-/B-n,8.030 Y-99/Y-98 98.933257	100 202 msec B-/B-n,7.080 Y-100/Y-99 99.935351	101 118 msec B-/B-n,9.510 Y-101/Y-100 100.94051
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	102 69 msec B-/B-n,8.820 Y-102/Y-101 101.94301