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:
“Like their personal lives, women’s history is fragmented, interrupted; a shadow history of human beings whose existence has been shaped by the efforts and the demands of others.”
—Elizabeth Janeway (b. 1913)
“What would we not give for some great poem to read now, which would be in harmony with the scenery,—for if men read aright, methinks they would never read anything but poems. No history nor philosophy can supply their place.”
—Henry David Thoreau (1817–1862)
“All history is a record of the power of minorities, and of minorities of one.”
—Ralph Waldo Emerson (1803–1882)