Barium , 99%metalsbasis , 7440-39-3
Synonym(s):
Barium element
CAS NO.：7440-39-3
Empirical Formula: Ba
Molecular Weight: 137.33
MDL number: MFCD00134031
EINECS: 231-149-1
PRODUCT Properties
| Melting point: | 725 °C(lit.) |
| Boiling point: | 1640 °C(lit.) |
| Density | 3.6 g/mL at 25 °C(lit.) |
| storage temp. | water-free area |
| solubility | reacts with H2O; slightly soluble in ethanol |
| form | rod |
| color | Silver-gray |
| Specific Gravity | 3.51 |
| Resistivity | 50.0 μΩ-cm, 20°C |
| Water Solubility | soluble with H2 evolution in cold H2O and hot H2O; slightly soluble alcohol; insoluble benzene [CRC10] |
| Sensitive | air sensitive, moisture sensitive |
| Merck | 13,967 |
| Exposure limits | TLV-TWA 0.5 mg/m3 (for soluble compounds)
(ACGIH and MSHA); IDLH (for
soluble compounds) 250 mg/m3 (NIOSH).
. |
| Stability: | Stability Reacts vigorously or violently with acids, water, tetrachloromethane, small halogenated hydrocarbons. Should be stored under an inert material such as petroleum ether to exclude air. Flammable. |
Description and Uses
Barium is a flammable, silver white or yellowish metal in various forms including powder. Barium mayignite spontaneously in air in the presence of moisture,evolving hydrogen. Molecular weight=137.34; Boilingpoint=1640℃; Freezing/Melting point=725℃; Vaporpressure=10 mmHg at 1049℃. Hazard Identification(based on NFPA-704 M Rating System): Health 2,Flammability 4, Reactivity 3 (water reactive).
The element is used in metallurgy, and its compounds
in pyrotechnics, petroleum mining, and radiology.
Metallic barium has few industrial uses. It has been
historically used to scavenge air in vacuumtubes. There,
the metal is used as a getter in electron tubes to perfect
the vacuum by combining with final traces of gases. It
is also used as a deoxidizer in copper refining, and as
a constituent in certain alloys. The alloy with nickel
readily emits electrons when heated and, for this reason,
is used in electron tubes and in spark plug electrodes.
The presence of barium (atomic number 56), observed
after uranium (atomic number 92) had been bombarded
by neutrons, was the clue that led to the recognition of
nuclear fission (1939).
The most important use of elemental barium is as
a scavenger removing last traces of oxygen and other
gases in television and other electronic tubes. Additionally,
an isotope of barium, 133Ba, is routinely used as
a standard source in the calibration of gamma ray detectors
in nuclear physics studies.
Safety
| Symbol(GHS) |    GHS02,GHS05,GHS06 |
| Signal word | Danger |
| Hazard statements | H228-H260-H301-H314 |
| Precautionary statements | P210-P231+P232-P260-P280-P303+P361+P353-P304+P340+P310-P305+P351+P338 |
| Hazard Codes | C,Xi,F |
| Risk Statements | 25-26-34-36/37/38-14/15-11 |
| Safety Statements | 23-26-36-36/37/39-45-43-36/37-16 |
| RIDADR | UN 3264 8/PG 3 |
| OEB | C |
| OEL | TWA: 0.5 mg/m3 |
| WGK Germany | 3 |
| RTECS | CQ8370000 |
| TSCA | Yes |
| HS Code | 2805 19 10 |
| HazardClass | 8 |
| PackingGroup | III |
| Toxicity | An element; the heaviest of the stable alkaline earths. Barium sulfate is used as a diagnostic aid in radiology due to its radio-opaqueness and, because of its insolubility and lack of absorption, it is safe barring iatrogenic episodes. Poisoning usually results from deliberate or accidental ingestion of soluble barium compounds. The Ba2+ ion is a muscle poison due to the blocking of the K1 channels of the Na+/K+ pump in cell membranes. Because cases of barium poisoning are accompanied by severe hypokalemia, potassium infusion is an effective antidote. The toxicity of barium compounds depends on their solubility, with the free ion being readily absorbed from gastrointestinal tract or lung, whereas the sulfate is essentially unabsorbed. Thus, administration of soluble sulfates immediately after ingestion is another effective antidote. |
| IDLA | 50 mg Ba/m3 |
