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Name: Strontium Symbol: Sr
Atomic Number: 38
Atomic Weight: 87.62
Group: Alkali Earth Metal
Melting Point: 769.0 degrees C
Boiling Point: 1384.0 degrees C
Where is it found: In the minerals celestite and strontianite
Density in natural state: 2.54 g/cm
Isotopes:
Naturally Occurring Isotopes
| Isotope |
Atomic mass (ma/u) |
Natural abundance (atom %) |
Nuclear spin (I) |
Magnetic moment (m/mN) |
| 84Sr |
83.913430 (4) |
0.56 (1) |
0 |
|
| 86Sr |
85.9092672 (28) |
9.86 (1) |
0 |
|
| 87Sr |
86.9088841 (28) |
7.00 (1) |
9/2 |
-1.09283 |
| 88Sr |
87.9056188 (28) |
82.58 (1) |
0 |
Radiosotopes
| Isotope |
Mass |
Half-life |
Mode of decay |
Nuclear spin |
Nuclear magnetic moment |
| 80Sr |
79.92453 |
1.77 h |
EC to 80Rb |
0 |
|
| 81Sr |
80.92322 |
22.3 m |
EC to 81Rb |
1/2 |
0.544 |
| 82Sr |
81.91840 |
25.36 d |
EC to 82Rb |
1/2 |
|
| 83Sr |
82.91756 |
1.350 d |
EC to 83Rb |
7/2 |
-0.898 |
| 85Sr |
84.912936 |
64.85 d |
EC to 85Rb |
9/2 |
-1.001 |
| 89Sr |
88.907455 |
50.52 d |
b-
to 89Y |
5/2 |
-1.149 |
| 90Sr |
89.907738 |
29.1 y |
b-
to 90Y |
0 |
|
| 91Sr |
90.91020 |
9.5 h |
b-
to 91Y |
5/2 |
-0.887 |
| 92Sr |
91.91098 |
2.71 h |
b-
to 92Y |
0 |
Abundance: 2.6 log [(# atoms of elements/# atoms of silicon) x 1E6]
How is it obtained?: This metal can be prepared by using electrolysis, which
is how it is usually obtained commercially, or it can be isolated by the
reduction of strontium oxide. (This reaction is shown below.)
6SrO + 2Al ----> 3Sr + Sr3Al2O6
Chemical Properties: The chemical properties of strontium are quite similar
to that of calcium. Strontium tends to have a very violent reaction when
it is exposed to air, which allows it to burn a brilliant red color that is used
in a lot of fireworks. (The reaction of strontium and air is below.)
2Sr(s) + O2(g) ----> 2SrO(s)
In addition, Strontium has two more electrons than the noble gas
krypton, so it tries to give away two electrons when it is reacting.
Compounds: Some common compounds that Strontium is involved in are strontium
carbonate, strontium nitrate, strontium chloride, and strontium chromate.
The main uses for these are in color television picture tubes as well as in
fireworks.
Strontium's Structure:
This is a picture of the physical structure of strontium. Strontium
uses the "crystal lattice" structure, in which there is a very organized pattern
of molecules.
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