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Dalton's Atomic Theory
Here are four basic ideas that Dalton incorperated into his theory:
- All elements are composed of atoms, which are indivisible and indistructable.
- All atoms of the same elements are the same, therefore they have the same masses.
- All atoms of different elements are different, therefore they have different masses.
- Compounds are formed by the joining of atoms of two or more elements. In any compound, the atoms of the different elements in the compound are joined in whole number ratios(i.e. 1-2, 1-4, 3-5, etc.).
These theories help to support three of the most used and known theories in the chemistry world:
The Law of Conservation of Mass:
This is the easiest of the trio of laws. In the simpilist of terms, it is saying what goes in must come out. The mass of the reactants that go into a chemicle reaction must be the same as the mass of the products.
The Law of Definite Proportions:
This law sounds very difficult to understand, but if you break it down into simple terms, it is a lot easier. For a certain compound, the elements that make it up always combine in the same ratio everytime. For example, in water, H20, there are always two Hydrogen atoms to one Oxygen Atom. Never will you see water as five Hydrogen atoms to two Oxygen atom.
The Law of Multiple Proportion:
This law is, quite literally, the basis for all of chemistry. Don't let this law scare you, it may sound tricky, but it really isn't. This law states that in any compound, the elements of that compound always combine in simple whole number ratio. For example, in water, H2O, the ratio of Hydrogen atoms to Oxygen atoms is 2 to 1. The ratio isn't 2.23 to 1.01, it is 1.00 to 2.00. This makes sence because with Dalton's Theory you can't reak atoms up, so therefore can' have 2 and 23/100 Hydrogen atoms and 1 and 1/100 Oxygen atoms.
If you are still confused look at more of [Dalton Atomic Theory]
And if you still need some help, there's still more [here!]]
After many years of scientific revolutions and technilogical breakthroughs, some revisions were made to Dalton's Atomic Theory. To see these new revisions, go to NewRevisions.
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