Pick a little, talk a little, pick a little, talk a little,
Cheep cheep cheep, talk a lot, pick a little more
These lyrics from the musical “Music Man” summed up the way science was done for centuries. OK, the lyrics referred to a group of gossiping ladies, but the outcome was the same. The Greek and Roman philosophers debated, discussed, and sometimes even attacked one another. But the mode of discovery was talk. There was no experimentation—the idea had not been thought of yet. So science did not develop very far and there was no reliable way to establish what was true and what was false.
While it must be assumed that many more scientists, philosophers and others studied the composition of matter after Democritus, a major leap forward in our understanding of the composition of matter took place in the 1800s with the work of the British scientist John Dalton. He started teaching school at age twelve, and was primarily known as a teacher. In his twenties, he moved to the growing city of Manchester, where he was able to pursue some scientific studies. His work in several areas of science brought him a number of honors. When he died, over 40,000 people in Manchester marched at his funeral.
Dalton studied the weights of various elements and compounds. He noticed that matter always combined in fixed ratios based on weight, or volume in the case of gases. Chemical compounds always contain the same proportion of elements by mass, regardless of amount, which provided further support for Proust’s law of definite proportions. Dalton also observed that there could be more than one combination of two elements.
From his experiments and observations, as well as the work from peers of his time, Dalton proposed a new theory of the atom. This later became known as Dalton’s atomic theory. The general tenets of this theory were as follows:
Dalton’s atomic theory has been largely accepted by the scientific community, with the exception of three changes. We know now that (1) an atom can be further sub-divided, (2) all atoms of an element are not identical in mass, and (3) using nuclear fission and fusion techniques, we can create or destroy atoms by changing them into other atoms.
Use the link below to do the exercise. Read the sections and take the quiz at the end.
SLG Chem1 LG 3.1 Dalton's Atomic Theory -atomic nature of matter Part 1-A and 1-B.pdf
CHEM 130 • Yuh-lng junior college of health care & management
7. TABAL Newton, Atoms molecules and ions (daltons atomic theory).pptx
CHEM E-1B • Harvard University
01. List four key features of Daltons atomic theory. Q2. When it.docx
CHEMISTRY MISC • Ahfad University for Women
Dalton's atomic theory states that all elements are composed of atoms.docx
CHEMISTRY 101 • Colorado Mountain College, Vail Valley
Lesson 1 - Atom, Laws of Matter, & Daltons Atomic Theory.pdf
CHEMISTRY 12 • San Francisco State University