Science 8 Chemistry

Physical Science - Content kinetic molecular theory (KMT) kinetic molecular theory (KMT): explains how particles move in different states atomic theory and models atomic theory: provides evidence for the existence of atoms and molecules models: models can be used to represent: the arrangement and motion of particles in different phases the arrangement of and forces that bind protons, neutrons, and electrons in an atom the quarks and leptons in protons, neutrons, and electrons protons, neutrons, and quarks protons, neutrons, and quarks: protons and neutrons (made of quarks) are held together in the nucleus by a strong nuclear force electrons and leptons electrons and leptons: electrons (a type of lepton) are held at a distance from the nucleus through electromagnetism

Kinetic Molecular Theory KMT: All matter is made of very small particles There are spaces between the particles The particle are in constant motion. They collide with each other and their container Energy makes the particles move. When energy is added, the particles move faster https://ed.ted.com/lessons/the-invisible-motion-of-still-objects-ran-tivony https://play.kahoot.it/#/k/d349363d-4796-499e-8e18-9c05a1d2906c

Examining KMT The purpose of this modelling activity is to understand how the empty spaces between molecules affects the volume of the mixtures of different substances The spaces between particles allow the volume of the mixture of two substances to be less than the sum of the volume before mixing because the particles of one substance fill some of the space between the other particles

Examining KMT The angry paint can We did this demo to show that the spaces between particles and the collisions between the particles and their container is different in different states: Solid particles are close together and fixed in position. They vibrate. Liquid particles are slightly farther apart and can slide past each other Gas particles fly about, taking up all the space available to them In reacting the lycopodium, carbon dioxide gas was produced, with the particles spreading out, the volume of the paint can could only contain them by dramatically increasing the pressure. This increase blew the top off.

Atomic Theory https://ed.ted.com/lessons/the-2- 400-year-search-for-the-atom- theresa-doud A 2400 year old theory that the ATOM is the smallest particle that matter can be chemically broken into.

Atomic Theory John Dalton- observed how matter combined and broke down in regular ratios. In 1805, he published a modern atomic theory and supported it with scientific observations. It was accepted by scientists of the time. Everything is composed of atoms, which are the indivisible building blocks of matter and cannot be destroyed. All atoms of an element are identical. The atoms of different elements vary in size and mass. Compounds are produced through different whole-number combinations of atoms. A chemical reaction results in the rearrangement of atoms in the reactant and product compounds Source: Boundless. “John Dalton and Atomic Theory.” Boundless Chemistry. Boundless, 26 May. 2016. Retrieved 29 Nov. 2016 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/atoms-molecules-and-ions-2/history-of-atomic-structure- 32/john-dalton-and-atomic-theory-197-6138/

Atomic Theory In 1897 J.J Thomson discovered the electron, leading to his proposing the chocolate chip cookie model of the atom: Negatively charged electrons are like chocolate chips, supended in the positively charged “cookie crust” of each atom

Ernest Rutherford In 1909, Rutheroford performed the famous gold foil experiment Led the to development of the concept of a nucleus: a dense core of positive charge with the negative electrons moving around it.

Atomic Theory In 1913, another of Thompson’s students, Niels Bohr applied quantum theory to come up with the model of the electrons only being found in specific orbitals around the atom. This model explained how specific amounts of energy are absorbed and emitted by different elements.

Atomic Theory In 1932, Chadwick discovered the neutron The neutron is an uncharged particle of equal mass to a proton The neutrons were added to the protons in the nucleus of the atom The Bohr model became for explaining the behavior of matter and elements in chemistry

Atomic Theory While the Bohr Model is used in school to explain that periodic table and compounds, physicists weren’t done. In 1925, Schrodinger came up with wave mechanics, describing the parts of the atom as interacting like a wave In 1926, Heisenberg. applied mathematics to prove that an electron’s position and velocity could not be identified at the same time The two ideas combined to create the electron cloud model of the atom. The nucleus stayed the same, but clouds were used to show you where you have a higher probability of finding electrons. https://play.kahoot.it/#/k/3c62bf03-8810-41a5-932f-9398a095b711

Atomic Theory In the second half of the 20th century, further discoveries- and the explanations for those discoveries- have led to the development of the standard model https://www.youtube.com/watch?v=PHP13tTjidA The standard model explains that: protons are made of three smaller particles called quarks: 2 up quarks and 1 down Neutrons are made of three smaller particles called quarks: 1 up quark and 2 down electrons are one type of lepton

Atomic Theory There are four forces in the universe: Weak force, Strong force, Electromagnetic force, Gravity. Standard model explains the influence of Strong, Weak and Electomagnetic force at the subatomic level. Gravity acts infinitely, but is the weakest force and can’t be fit into standard theory Electromagnetism also acts infinitely, but is the second strongest force Strong and weak force only act at the Subatomic level- we aren’t aware of their effects on us. Strong force is the strongest force and acts over the second shortest distance Weak force is the third strongest force and acts over the shortest distance. Protons and neutrons are held together in the nucleus by strong force Electrons are held at a distance from the nucleus by electromagnetic force

Atomic Theory Clearly, the atomic theory is more complex today, and while it answers many questions about the universe, it is still incomplete It cannot answer Big questions about Dark Matter and Antimatter in the formation of the Universe. https://www.youtube.com/user/CERNTV https://play.kahoot.it/#/k/a79ec876-9928-40d9-aa9b-c2559e3f06c0 https://ed.ted.com/lessons/if-matter-falls-down-does-antimatter-fall-up-chloe- malbrunot#review

KMT and Atomic Theory So what do we do with this? Research, build a model and explain of the levels of development of the KMT or Atomic Theory Explain how the model, at the level of development you investigated, is useful Who is it useful to? How could this group use it? Explain how advanced a Canadian Citizen’s understanding of KMT and Atomic Theory should be, at a minimum, and why.