learning log
atoms & nuclear chemistry
The third week of the school years started with notes and alot of it. The idea of atoms was first proposed by Democritus in 400 BCE. However, the idea was discared until the 18th century when scientists began fing evedence supporting the idea. The three main laws of the Atomic theory are the Law of Conservation of Mass, the Law of Definate Proportions, and the Law of multiple proportions. Baisicly with out all the fancy words the law of consevation of mass is durring a chemical reaction mass is neither created nor destroied. Second, the law of definate proportions is that a chemical compond cantins the same elements is the same proportions by mass regardless of how big the sample is. Lastly the law of multiple proportions is that two or more different compounds contain two or more of the same elements their masses are a ratio of two small whole numbers. The structure of atoms is a small nucleus, comprised of protons and neutrons, surrounded by an electron clound inwhich the electrons move freely. Protons and neutrons are each a type of hadrons and a type of baryons and and are composed of three quarks. Protons have two up quarks and one down quark and neutrons have two down quarks and one up quark. Another type of Hadron are mesons which are composed of onequark and one anti-quark. Electrons are under their own type of particles called Leptons along with muons, tau, and neutrinos. Many experements were conducted to learn these parts of an atom including the cathod ray experement, the oil drop experement, and most importantly the gold foil experement. The gold foil experement had a a thin gold foil enclosed except of one lazer shooting alpha particles. The scientest and Rutherford expected the negitive alpha particles to pass straight through the foil and for the most part they did. However, on few occasions the particles bent on their otherwise straight path and even stranger sometimes they even bounced back. From these observations the conclusion was that there was a positive small center in the middle of the atom. This was the discovery of the nucleus. Scientists measue the number of atoms in moles. The number of atoms in one mole is approximately 6.022x10^23. Then, to find the number of moles in grams by multiplying the molar mass (same as the atomic mass) by the number of moles. Lastly, neuclear chemistry involves radioactivity on a nuclear level. Its known that there is a force overcoming the repusive force of the protons in the nucleus called the very strong nuclear force. This force and the repulsive force do a constant balancing act to keep the atom stable. However with greater mass the harder it is to maintain balance. This unbalanced atims are radioactive atoms. These react with alph beta and gama particles to decompose and fuse together to form different elements.
lab abstract
The objective of the lab was to measure the amount of water molecules on a salt. First measure the mass of the pocelain cup and then the cup with the salt. With this you can find the salts mass. THen you heat the pocelain cup with the salt over a buncen burnner and cover it once you hear the salt start to crackel. You then let it stay over the flame for about 10 minutes. Then let it cool and retake the mass. Once you find the mass of the salt. Afterward the difference is the amont of water molecules the evaporated. Next, you sould convert the mass of salt and the mass of water into moles and compare the data. The accepter value and the ratio that two groups attained is 7:1.