Compounds - Rathjen Science!
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QOD #50 • Compare and contrast the physical properties of a paperclip and an eraser. (hint: Use a Venn Diagram) Compounds & Equations • When two or more atoms join together and act as an independent molecules unit, they are called______________. • When two or more elements join together in a chemical bond, they compound become a ___________________. • Example: NaCl Na (Sodium) + Cl (Chlorine) NaCl (Sodium Chloride) • Compounds cannot be physically ______________ separated. • A compound is a new substance _____________ that is different from each of the individual elements that make it up. • Ex. HβO - one water molecule contains two atoms of hydrogen and one atom of oxygen bonded together acting as one unit. • Ex. πͺππ π―ππ πΆππ - one molecule of table 12 carbon atoms, ____ 22 sugar contains ____ 11 hydrogen atoms, and ____oxygen atoms. Compound Names • Read names for most chemical formulas left to right. • Many compound names add the endings –ate or –ide to the last element. • Some compounds add a prefix to an element name that says how many atoms of each element are in the compound. – CO is carbon monoxide – COβ is carbon dioxide QOD #50- Match the chemical name with the chemical formula… Carbon monoxide ZnCl Carbon dioxide HβOβ Sodium chloride COβ Hydrogen peroxide CO Zinc chloride NaCl Types of Bonds - Challenge share • Covalent Bonds – atoms __________ one or more pairs of valence (outermost) electrons. – Happens between two nonmetals. – Can share more than one pair of electrons. – The more shared pairs, the stronger the bond. – Ex. HβO - water gain or _______ lose • Ionic Bonds – atoms ______ electrons – Between a metal and a nonmetal – Ex. NaCl – salt • Sodium loses a valance electron making it a positive ion. • Chlorine gains an electron which makes it a negative ion. • Both atoms are now stable and attracted to each other. • Metallic Bonds – two or more metals pooled valence electrons. share ________ –Ex. Aluminum –Pooled electron sharing enables metals to be malleable and ductile. Drawing molecules: • The smaller the atomic number, the smaller the atom. Ex. Helium is smaller than Zinc. Gases • Oxygen O2 • Nitrogen N2 • Hydrogen H2 • Carbon dioxide • Carbon monoxide • Sulfur dioxide CO2 CO SO2 • Nitrogen dioxide NO2 • Nitrogen monoxide (nitric oxide) NO • Dinitrogen oxide (nitrous oxide) N2O • Chlorine Cl2 • Hydrogen chloride HCl • Ammonia NH3 Acids • Hydrochloric acid • Sulfuric acid • Nitric acid • Phosphoric acid • Carbonic acid HCl H2SO4 HNO3 H3PO4 H2CO3 Bases • Sodium hydroxide NaOH • Potassium hydroxide KOH • Calcium hydroxide Ca(OH)2 Salts • Sodium chloride • Sodium carbonate • Calcium carbonate • Calcium sulfate • Ammonium sulfate • Potassium nitrate NaCl Na2CO3 CaCO3 CaSO4 (NH4)2SO4 KNO3 3-D Compounds • Due Friday • Choose a compound to make a 3-D model out of. Must have at least 3 atoms. • Do not buy anything – use food items. • Include a key that has the compound name, formula, and indicates what the atoms are. • Extra credit for indicating the type of bond (covalent, ionic, metallic). Chemical Equations • Reactants – the starting substances in a chemical reaction. • Products – the substances produced by a chemical reaction. Reactants C (Carbon) + Product Oβ (Oxygen) COβ (Carbon dioxide) Examples Photosynthesis 6COβ + 6HβO Carbon water _________ + ___________ dioxide C6 H12 O6 + 6Oβ sugar + ________ oxygen __________ Cellular Respiration C6 H12 O6 sugar _________ + 6Oβ oxygen + __________ 6COβ + 6HβO Carbon + _________ water ________ dioxide • The Law of Conservation of Mass applies in a chemical reaction – what goes in, must come out!
