Every living and nonliving things is made up of matter. MATTER: anything that has mass & takes up space. What does all matter have in common?

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1 the basics

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3 Every living and nonliving things is made up of matter MATTER: anything that has mass & takes up space What does all matter have in common?

4 Smallest unit of matter ALL matter is made of particles called atoms Always in motion and bumping into each other Kinetic energy the energy of motion

5 Have a definite shape & volume Molecules are packed tightly together in a pattern DO move more of a vibration

6 Have a definite volume but NO definite shape Not in any arrangement Molecules are loosely packed and flow against each other loosey goosey = loosey liquids

7 Have no definite shape and no definite volume Not in any arrangement Molecules are far apart and can move freely

8 Matter either looses or absorbs energy when it changes states Solid liquid = melting Solid gas = sublimation Liquid solid = freezing Liquid gas = vaporization Gas liquid = condensation Gas solid = deposition

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10 Two major parts Nucleus Positively charged Electron cloud Negatively charged

11 Proton Positively charged Found in nucleus The # of these determines the elements Contributes to mass Neutrons No charge neutral Found in nucleus Contributes to mass o +

12 Electron Negatively charges Located in electron cloud So small contribute very little mass The outer most electrons are used in bonding (valence electrons)

13 A substance made up of atoms that all have the same number of protons CAN NOT be broken down into simpler substances EX: Gold & Oxygen

14 Arrangement of elements ordered by: Atomic number Electron configuration Chemical properties

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16 Element name Unique for each element Usually from Latin based words due to ancient Romans attempting to identify elements Sometimes named after scientists who discovered them (ego much?) Must be approved by committee Element symbol Some names are longggg or hard to pronounce Some based on name of element others are based in different language First letter is ALWAYS capitalized 12 Mg Magnesium

17 Atomic number The number of protons found in the nucleus Atomic mass The total mass of all the protons & neutrons Each proton & each neutron are equal to 1 AMU (atomic mass unit 12 Mg Magnesium atomic mass atomic number = # of neutrons

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19 Contain only one type of atom Sodium (Na) Cannot be broken down into simpler substance by any physical or chemical means Can exist as atoms or molecules

20 Contain atoms or 2 or more different elements Bonded together in a specific pattern Can be broken down by chemical means but not physical means Sodium Chloride (NaCl) Has different properties than its components

21 Contains 2 or more substances (elements or compounds) that are NOT bonded together Can be separated physically Salt Water (NaCl + H 2 O) Retains many of the same properties of its components

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23 The outer most electrons that are used in bonding Determine the reactivity of an atom Reactivity = how likely an atom is to bond with another atom Can use periodic table to determine reactivity

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25 Strongest of chemical bonds Formed by the attraction between two oppositely charged ions Ion = atom that has lost or gained an election causing it to have a charge Valence electrons are stolen or taken

26 Strong bond Sharing of electrons between atoms Makes the outer shell of electron cloud feel full

27 A very weak bond Between molecules not atoms! Between partial negative region of one molecule and a positive region of another WATER!!!

28 since we re talking about hydrogen bonds.

29 Nearly 70% of your body is made of water Water is where most cellular events take place Water helps move nutrients and other substances into and out of your cells So. It s kind of important!

30 Heat Stores heat efficiently Heats more slowly and stores heat longer than most substances This allows our bodies to maintain a constant state

31 Water bonds to itself and other substances Cohesion Hydrogen bonds between water molecules cause an attraction to each other Allows water to form drops and thin films Also causes surface tension prevents water surface from stretching or breaking easily

32 Adhesion Water molecules are also attracted to other substances

33 Universal solvent Many substances dissolve in water making solutions because of polarity Solution = a mixture in which one or more substances are evenly distributed in another substance Non-polar molecules DO NOT dissolve in water EX: oil and water

34 When solutions are made with water as a solvent it may add or reduce hydrogen ions This determines the acidity or alkalinity of a solution

35 Acids Compounds that form hydrogen ions when dissolved in water Bases Compounds that reduce the concentration of hydrogen ions when dissolved in water

36 Measures the acidity or alkalinity of a substance

37 sounds scary but it s not!

38 A process that involves the rearrangement of the molecular or ionic structure of a substance Six different types Combustion Neutralization Synthesis Decomposition Single displacement Double displacement

39 During chemical reactions, energy is both absorbed and released. Some absorb more than they release and others release more than they absorb Some energy must be absorbed to start a chemical reaction = activation energy

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41 Endothermic: a chemical reaction that absorbs more energy than it releases Exothermic: a chemical reaction that releases more energy than it absorbs

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44 Carefully rinse and dry off the thermometer Carefully dump out the contents in the test tube down the sink. Rinse out all materials. Carefully and to your best ability dry it. Rinse your test tube rack off. Place the clean test tube back. Carefully remove the beaker from the hot plate. Dump the water into the sink. Rinse the beaker and dry it off. Place it back on the hot plate when you re done. Rinse your graduated cylinder and dry them out to the best of your ability.

45 Occurs when a compound containing carbon and hydrogen reacts with oxygen Creates water vapor, carbon dioxide, and heat CH 4 2 O 2 CO 2 2 H 2 O methane oxygen carbon dioxide water

46 Happens when an acid and a base are added to each other Complete neutralization occurs if the same amount of hydrogen and hydroxide ions are present and salt and water are formed HCl NaOH NaCl H 2 O hydrogen chloride sodium hydroxide sodium chloride water

47 Occurs when simple compounds combine to make a more complex compound 2 Na Cl 2 2 NaCl

48 Occurs when a compound or molecule breaks down into simpler ones 2 H 2 O 2 2 H 2 O O 2

49 Occurs when a pure element switches places with an element in a compound Mg 2 HCl H 2 MgCl 2

50 Occurs when the cations of two compounds switch to form new compounds HCl AgNO 2 AgCl HNO 2

51 Color change Gas production Light emission Odor Precipitates Temperature change

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53 Symbolic representation of a chemical reaction Uses symbols and chemical formulas Chemical formulas represent a molecule using the element symbols and numbers EX: CO 2

54 6 CO H 2 O C 6 H 12 O O 2 ( The stuff that goes into ) ( The stuff that comes out ) the reaction A chemical equation has three sections Reactants Products Yield YIELD of the reaction

55 6 CO H 2 O C 6 H 12 O O 2 Subscript shows the number of atoms for that element Coefficient Shows the number of molecules

56 1. Identify and count the number of each element in the equation 2. The goal is to have an equal number of atoms for each element on both sides - We use multiplication Let s give it a try

57 This one is easy! 6 CO H 2 O C 6 H 12 O O 2 reactants products

58 Let s try another one Na 2 + F 2 NaF 2 reactants products

59 Balancing Chemical Equations Worksheet

60 Law of Conservation of Mass Mass cannot be created or destroyed Law of Conservation of Matter Matter cannot be created or destroyed but it can change forms