John Dalton

John Dalton
  

ALL ABOUT JOHN DALTON
➝ He is The Father of Modern Atomic Theory.
Born: 6 September 1766
Birthplace: Eaglesfield, Cumberland, England
Died: 27 July 1844
Best Known As: The weather pioneer who advocated atomic theory



BRIEF BACKGROUND
John Dalton was born in England in 1766. He was brought up as a Quaker and at 12 years of age was running the school. He kept a journal of meteorological observations for 57 years and is an acknowledged pioneer of that science. He was honoured for his work on an atomic theory for the elements, was elected to various learned academies, and throughout remained a humble man and a dedicated teacher.


ACHIEVEMENTS
• He revived the atomic theory, which he formulated in the first volume of his New System of Chemical Philosophy (2 vol., 1808-27).
• He had already applied the concept to a table of atomic weights (1803), in a paper (1805) on the absorption of gases, and in developing his famous law of partial pressures, known also as Dalton's law.
• His interest in weather conditions led him to keep daily records from 1787 and to write Meteorological Observations and Essays (1793).
• Dalton, himself afflicted with color blindness, investigated (c.1794) the condition, known also as Daltonism.
• From 1793 he taught mathematics and physical sciences at New College, Manchester.
• He was a member of the Royal Society (from 1822) and in 1825 received its medal for his work on the atomic theory.


THE ATOMIC THEORY
Dalton's theory was based on the premise that the atoms of different elements could be distinguished by differences in their weights. He stated his theory in a lecture to the Royal Institution in 1803. The theory proposed a number of basic ideas:

• All matter is composed of atoms
• Atoms cannot be made or destroyed
• All atoms of the same element are identical
• Different elements have different types of atoms
• Chemical reactions occur when atoms are rearranged
• Compounds are formed from atoms of the constituent elements.

Using his theory, Dalton rationalised the various laws of chemical combination which were in existence at that time. However, he made a mistake in assuming that the simplest compound of two elements must be binary, formed from atoms of each element in a 1:1 ratio, and his system of atomic weights was not very accurate - he gave oxygen an atomic weight of seven instead of eight.
Despite these errors, Dalton's theory provided a logical explanation of concepts, and led the way into new fields of experimentation.



* Billiard Ball Model (1803) - John Dalton viewed the atom as a small solid sphere. He really got the "ball" rolling for modern chemistry!


EVENTS THAT HAPPENED DURING HIS ERA
1803
January - March
* January 5 – William Symington demonstrates his Charlotte Dundas, the "first practical steamboat". : steamboat Charlotte Dundas.
* January 30 – Monroe and Livingston sail for Paris to discuss, and possibly buy, New Orleans; they end up completing the Louisiana Purchase.
* February 21 – Edward Despard and 6 others are hanged and beheaded for plotting to assassinate King George III and to destroy the Bank of England.
* February 24 – Marbury v. Madison: The Supreme Court of the United States establishes the principle of judicial review.
* February 25 – A major redistribution of territorial sovereignty within the Holy Roman Empire is enacted via an act known as the Reichsdeputationshauptschluss.
* March 1 – Ohio is admitted as the 17th U.S. state, retroactive from August 7, 1953.
* March 9 – Aargau becomes a Swiss canton.

April – June
* April 30 – Louisiana Purchase is made by the United States from France.
* May – The First Consul of France Citizen Bonaparte begins making preparations to invade England.
* May 18 – The United Kingdom resumes war on France after France refuses to withdraw from Dutch territory.
* May 19 – Master Malati, a Coptic Christian leader, is beheaded by a Muslim mob in Cairo, Egypt.

July – September
* July 4 – The Louisiana Purchase is announced to the American people.
* July 5 – The convention of Artlenburg leads to the French occupation of Hanover (which had been ruled by the British king).
* July 23 – Robert Emmet's uprising in Ireland begins.
* July 26 – The wagonway between Wandsworth and Croydon is opened, being the first public railway line of the world.
* August 3 – The British begin the Second Anglo-Maratha War against Sindhia of Gwalior.
* September 3 – William Wordsworth wrote "Upon Westminster Bridge"
* September 20 – Irish rebel Robert Emmet is executed.
* September 23 – Battle of Assaye (India): British-led troops defeat Maratha forces.

October – December
* October 20 – The Senate ratifies the Louisiana Purchase Treaty, doubling the size of the United States.
* November 18- Battle of Vertières: The Haitian army led by Jean-Jacques Dessalines defeats the army of Napoleon.
* November 30 – At the Cabildo building in New Orleans, Spanish representatives Governor Manuel de Salcedo and the Marqués de Casa Calvo, officially transfer the Louisiana Territory to French representative Prefect Pierre Clément de Laussat (just 20 days later, France transfers the same land to the United States as the Louisiana Purchase).
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Sources:
http://www.abc.net.au/rn/science/ss/stories/s1427745.htm
http://www.csmate.colostate.edu/cltw/cohortpages/viney_off/atomhistory.html
http://www.answers.com/topic/john-dalton
http://www.abc.net.au/rn/science/ss/stories/s1427745.htm
http://answers.encyclopedia.com/question/were-john-dalton-main-accomplishments-84750.html