HomeLink Parent Portal is available for all MDUSD students and legal guardians. There are a variety of reasons to have a HomeLink Parent Portal account, and some of the benefits include the ability to check student grades (Middle & High Schools only), test scores, attendance, as well as other contact and registration features. 2.
When present in compounds barium exists usually in the Ba 2+ , divalent state. Barium dissolves in most aqueous acids except sulfuric acid, due to the formation of an insoluble protective layer of barium sulfate.
Barium: historical information. Barium was discovered by Sir Humphrey Davy at 1808 in England. Baryta (barium oxide, BaO) was distinguished from lime (calcium oxide, CaO) by Scheele in 1774. Elemental barium was isolated by Sir Humphrey Davy in 1808 who electrolysed molten baryta. Sometime prior to the autumn of 1803, the Englishman John Dalton was able to explain the results of some of his studies by assuming that matter is composed of atoms and that all samples of any given compound consist of the same combination of these atoms.