Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download The Atom - Taylorsville
Document related concepts
Transcript
The Atom Law of Conservation of Mass • Was discovered by Antoine Lavoisier • Helped moved alchemy to be chemistry • Mass cannot be created nor destroyed in normal chemical or physical processes. Aristotle – the four basic elements -Earth -Air -Water -Fire Democritus -Follower of Leucippus -An Atomist -Coined the word atomos meaning uncuttable or the smallest particle of matter 2000 years later John Dalton – School Teacher Five main points of Dalton's atomic theory 1. Elements are made of tiny particles called atoms. 2. All atoms of a given element are identical. 3. The atoms of a given element are different from those of any other element; the atoms of different elements can be distinguished from one another by their respective relative atomic weights. 4. Atoms of one element can combine with atoms of other elements to form chemical compounds; a given compound always has the same relative numbers of types of atoms. 5. Atoms cannot be created, divided into smaller particles, nor destroyed in the chemical process; a chemical reaction simply changes the way atoms are grouped together. Daltons Model of the Atom Cathode Ray Tube Plum Pudding Model of the Atom JJ Thompson Gold Foil Experiment – Ernest Rutherford Rutherford’s Model of the Atom Relative Mass Particle Symbol Charge Mass (kg) Number Location Around electrone-1 9.109x10-31 0 Nucleus proton p+ +1 1.673x10-27 1Nucleus neutron n0 0 1.675x10-27 1Nucleus Atomic Number: The number of protons in the nucleus of an atom Mass Number: The total number of protons and neutrons on a nucleus Atomic Number Symbol Atomic Mass Isotope: Atoms of the same element that have different masses Determining the number of protons neutrons and electrons in an isotope. 35 17 Cl Bromine-80 # of protons = atomic number 17 # of neutrons = mass number – atomic number 35 - 17= 18 # of electrons = # of protons in a neutral atom 17 # of protons = atomic number 35 # of neutrons = mass number – atomic number 80 – 35 = 45 # of electrons = # of protons in a neutral atom 35 Practice!! 1) Aluminum -27 protons-13 neutrons-14 electrons-13 2) Copper-65 protons-29 neutrons-36 electrons-29 3) 11 5B protons-5 neutrons-6 electrons-5 4) 131 Xe 54 protons-54 neutrons-77 electrons-54 protons-82 neutrons-126 electrons-82 5) Lead-208
