History
The discovery of all elements in the group led to controversies. The verification of those discoveries was difficult due to similarity of vanadium and group 6 element chromium, the chemical similarity of niobium and tantalum and the complicated setup which was necessary to produce a few atoms of dubnium.
Read more about this topic: Group 5 Element
Famous quotes containing the word history:
“As History stands, it is a sort of Chinese Play, without end and without lesson.”
—Henry Brooks Adams (18381918)
“To care for the quarrels of the past, to identify oneself passionately with a cause that became, politically speaking, a losing cause with the birth of the modern world, is to experience a kind of straining against reality, a rebellious nonconformity that, again, is rare in America, where children are instructed in the virtues of the system they live under, as though history had achieved a happy ending in American civics.”
—Mary McCarthy (19121989)
“In all history no class has been enfranchised without some selfish motive underlying. If to-day we could prove to Republicans or Democrats that every woman would vote for their party, we should be enfranchised.”
—Carrie Chapman Catt (18591947)