Hi Emily,
I can understand your frustration and urgency in needing to know which of Dalton's atomic theories were disproven and why. Let's break it down and hopefully I can help you out.
Firstly, it's important to know that Dalton's atomic theory is made up of four key principles. These principles include:
1. All matter is made up of tiny, indivisible particles called atoms.
2. Atoms of the same element are identical in size, mass, and chemical properties.
3. Atoms of different elements have different sizes, masses, and chemical properties.
4. Chemical reactions occur when atoms are rearranged, combined, or separated.
Now, as for which of these theories were disproven, it is actually the first and second principles that have been proven to be incorrect. Here's why:
1. The first principle, stating that all matter is made up of tiny, indivisible particles called atoms, has been disproven with the discovery of subatomic particles such as protons, neutrons, and electrons. These particles make up atoms and can be further broken down into even smaller particles.
2. The second principle, stating that atoms of the same element are identical in size, mass, and chemical properties, has also been disproven. We now know that atoms of the same element can have different masses due to the presence of isotopes, which are atoms with the same number of protons but different numbers of neutrons.
I hope this helps clear things up for you. Remember, scientific theories are constantly evolving and being refined with new discoveries and evidence. So while Dalton's atomic theory may not be entirely accurate, it was a groundbreaking theory that paved the way for our current understanding of the atomic world. Best of luck in your studies!
