The postulates of Dalton's atomic theory: which points do we still use today, and what have we learned since Dalton?
Log in garrettjmoore14 9 years agoPosted 9 years ago. Direct link to garrettjmoore14's post “Why is Daltons theory sti...” Why is Daltons theory still taught if it is not 100% accurate? • (281 votes) yuki 9 years agoPosted 9 years ago. Direct link to yuki's post “It is also helpful to thi...” It is also helpful to think about how science is always evolving-we are always learning new things and modifying existing theories to take into account new discoveries. That happened to Dalton's atomic theory, and that will likely to happen to many more theories to come! (407 votes) Hridanshu Ruparel 9 years agoPosted 9 years ago. Direct link to Hridanshu Ruparel's post “Why is not possible to fu...” Why is not possible to further separate atoms?? • (42 votes) Esther Dickey 9 years agoPosted 9 years ago. Direct link to Esther Dickey's post “Actually, it is. Atoms a...” Actually, it is. Atoms are made up of protons, neutrons, and electrons. However, if you remove any of these particles the atom will have different properties. An atom is the smallest particle of an element that has all the properties of the element. For example, sodium in its pure form reacts violently with water. When you take away one of its electrons, it becomes part of table salt and no longer reacts with water. (150 votes) Eryquin-Mor 9 years agoPosted 9 years ago. Direct link to Eryquin-Mor's post “In part 3 of the article,...” In part 3 of the article,(Compounds are combinations of 2 or more different atoms) how is it possible that we don't get affected by the different properties of the elements and get sick if chlorine is a TOXIC gas and sodium is a highly REACTIVE metal? • (21 votes) Matt B 9 years agoPosted 9 years ago. Direct link to Matt B's post “Sodium and chlorine are t...” Sodium and chlorine are toxic/explosive because they are unstable and therefore very reactive. If you look at the electrons in the shells, they want to react to fill their outer shell of electrons. Once they react, they exist as ions and then lose their property of being super-reactive because they then become stable. (59 votes) Danny 8 years agoPosted 8 years ago. Direct link to Danny's post “Why can't there be half a...” Why can't there be half an atom? And why are chemists so sure? • (18 votes) brettjsnyder 8 years agoPosted 8 years ago. Direct link to brettjsnyder's post “We say that an atom can't...” We say that an atom can't be cut in half, not because it can't actually be split (aka nuclear fission - reactor, bomb) but rather because the resulting parts would no longer be atoms the elements the you started with. Ex: you can't split a Helium atom because to do so would result in 1 or 2 Hydrogen atoms and some leftover bits - but it would no longer BE Helium. (66 votes) Pooja Goyal 8 years agoPosted 8 years ago. Direct link to Pooja Goyal's post “cant we put protons (h+) ...” cant we put protons (h+) into a nucleus of he (he+) to get nucleus of an new element • (9 votes) sedspqr 8 years agoPosted 8 years ago. Direct link to sedspqr's post “To do this would require ...” To do this would require nuclear fusion (combining smaller atomic nuclei to form a larger one), a process which is not yet quite possible in the lab. It would produce more energy than an atomic bomb would. (18 votes) Thadd Hudson 9 years agoPosted 9 years ago. Direct link to Thadd Hudson's post “Did Dalton make up anothe...” Did Dalton make up another theory that we can use instead of the one that was originally created? • (7 votes) Elijah Sy 9 years agoPosted 9 years ago. Direct link to Elijah Sy's post “Well there are several pa...” Well there are several parts to Dalton's theory. His only theory is the atomic theory and today we know that atoms can be destroyed by nuclear reactions but not by chemical reactions. Also, there are different kinds of atoms (differing by their masses) within an element that are known as "isotopes", but isotopes of an element have the same chemical properties. Hope that helped. But his theory was not 100% correct. -http://www.iun.edu/~cpanhd/C101webnotes/composition/dalton.html (11 votes) Sam D 9 years agoPosted 9 years ago. Direct link to Sam D's post “Didn't Antoine Lavoisier ...” Didn't Antoine Lavoisier propose the law of conservation of mass? • (8 votes) Matt B 9 years agoPosted 9 years ago. Direct link to Matt B's post “A peer reviewed journal, ...” A peer reviewed journal, ERIC, published "A Historical Note on the Conservation of Mass." This states in their abstract that this is not entirely true: "Although most historians of science attribute the formulation of the law of conservation of matter in chemical reactions to Antoine Lavoisier at the end of the eighteenth century, several earlier researchers had already assumed this law in their work. These researchers include Joseph Black, Henry Cavendish, M. V. Lomonosov, and Jean Rey." (9 votes) Vijeya Patel 9 years agoPosted 9 years ago. Direct link to Vijeya Patel's post “well as far as I understa...” well as far as I understand this concept,atoms cannot bee further divided but we know that atoms are further divided into fundamental particles as protons,electrons and neutrons.So why does this conclusion given by dalton sir still hold true?? • (7 votes) Ernest Zinck 9 years agoPosted 9 years ago. Direct link to Ernest Zinck's post “Many of Dalton's original...” Many of Dalton's original postulates of an atomic theory have had to be modified in the light of later discoveries. (8 votes) Erin Boyle 8 years agoPosted 8 years ago. Direct link to Erin Boyle's post “Why can you not add proto...” Why can you not add protons/neutrons/electrons to an atom? • (2 votes) Matt B 8 years agoPosted 8 years ago. Direct link to Matt B's post “You cannot add protons an...” You cannot add protons and neutrons because they are in the center of an atom and held tighly by the strong nuclear force. However, you can add electrons to atoms and this happens all the time: the gaining and losing of electrons is precisely what chemical reactions are! (13 votes) Rohan Jaswal 8 years agoPosted 8 years ago. Direct link to Rohan Jaswal's post “What is the difference be...” What is the difference between an element and molecule? • (4 votes) Abdülrezzak Bostani 8 years agoPosted 8 years ago. Direct link to Abdülrezzak Bostani's post “in summary:element - a b...” in summary: (4 votes)Want to join the conversation?
It is not nonexistent, however. This process occurs constantly in the core of the sun - basically, what you asked about is what gives Earth the energy necessary to support human life!
As far as chemical reactions go, the essential concept that chemical reactions involve atoms and molecules still remains.
In many other cases, chemists have to use the concept of electrons, protons, etc.
Dalton's atomic formed the basis of chemistry, but modern chemists have long since adapted their understanding to include later discoveries.
element - a basic substance that can't be simplified (hydrogen, oxygen, gold, etc...)
atom - the smallest amount of an element
molecule - two or more atoms that are chemically joined together (H2, O2, H2O, etc...)
compound - a molecule that contains more than one element (H2O, C6H12O6, etc...)
