'Joseph Black' (
April 16,
1728 -
december 6,
1799) was a
Scottish physicist and
chemist, known for his discoveries of
latent heat,
specific heat, and
carbon dioxide. He was a founder of
thermochemistry who developed many pre-
thermodynamics concepts, such as
heat capacity, and was the mentor for
James Watt. The
chemistry buildings at both the
University of Edinburgh and the
University of Glasgow are named after him.
Early years
Black was born in
Bordeaux, France, where his father, who was from
Belfast,
Ireland, was engaged in the wine trade. His mother was from
Aberdeenshire,
Scotland, and her family was also in the wine business. Joseph had twelve brothers and sisters.
[1] He entered the
University of Glasgow when he was eighteen years old, and four years later he went to
Edinburgh to further his medical studies.
Professional life
While at the University of Edinburgh, Black studied properties of
carbon dioxide (CO2).
[2]. One of his experiments involved placing a flame and mice into the carbon dioxide. Because both entities died, Black concluded that the air was not breathable. He named it 'fixed air' in
1754. In
1756 Black described how
carbonates become more alkaline when they lose carbon dioxide, whereas the taking-up of carbon dioxide reconverts them. He was the first person to isolate carbon dioxide in a perfectly pure state. This was an important step in the history of chemistry as it helped people to realize that air was not an element, but rather was composed of many different things. Black's work also aided in discrediting the belief in a fiery principle called
phlogiston.
In about 1750, Joseph Black developed the
analytical balance based on a light-weight beam balanced on a wedge-shaped
fulcrum. Each arm carried a pan on which the sample or standard weights was placed. It far exceeded the accuracy of any other balance of the time and became an important scientific instrument in most chemistry laboratories.
[3].
In
1757, he was appointed
Regius Professor of the Practice of Medicine at the
University of Glasgow.
In
1761, he discovered that when
ice melts it absorbs
heat without changing
temperature. From this he concluded that the heat must have combined with the ice particles and become
latent. This discovery was perhaps his most important, and the one on which his scientific fame chiefly rests. He also showed that different substances have different specific heats.
Personal life
Black was a friend of
James Watt, who first began his studies on steam power at Glasgow University in 1761. Black also was a member of
the Poker Club and associated with
David Hume,
Adam Smith, and the literati of the
Scottish Enlightenment. Black never married. He died in Edinburgh at the age of 71, and is buried there in
Greyfriars Kirkyard.
References
1. Lenard, p. 129
2. See [1]
3. See [2]
Further reading
★ Lenard, Philipp (1950). ''Great Men of Science.'' Translated from the second German edition, London: G. Bell and Sons, ISBN 0-8369-1614-X, pp. 126 ff.
★ Ramsay, William (1905). ''The Gases of the Atmosphere'', London: Macmillan.
External links
★
Black's experiments on Alkaline Substances
★
Joseph Black – Biography
★
Joseph Black – Britannica, 1911