1. What is an element? • • Pure Substance • Made up of one kind of atom • Homogeneous in structure • Cannot be broken down or separated Identified by a chemical symbol (ex. C) Classified as : Metal, nonmetal, metalloid 2. What is a compound? • Is a pure substance • Made up of 2 or more types of elements • Is homogeneous in structure • Can be broken down or separated by _chemical__ means • Smallest unit is a molecule • Identified by a chemical formula (H2O) • Created through a chemical change • Held together by a ___chemical bond____ • Examples: Sugar, Rust, Water, Carbon Dioxide 3. Complete the chart below using a periodic table Element Name Element Symbol Symbol Name Gold Mn Ag Magnesium Cu Mercury Zinc Fe Sodium 4. Lead Elements are Grouped By Type Metals • • • • • 5. Solid and Shiny Conduct Electricity and Heat Nonmetals • • • • Liquid/Gas Brittle Elements a. Symbol i. ______________________ ii. Not always first letter iii. Sometimes Latin Name 1. Ex. Gold = Au = Aurum Metalloids • • • 6. Writing Compounds a. Coefficient i. Number ___________ the element/compound ii. Tells you how many of the element/compound there are b. Subscript i. Number _____________ element ii. Tells you how many atoms of that element there are 7. Counting Atoms in a Compound Practice a. CaCO3 i. Ca = ii. C = iii. O = b. C9H8O4 i. C = ii. H = iii. O = c. Mg(OH)2 i. Mg = ii. O = iii. H = d. 2FeS2 i. Fe = ii. S = e. H2O + O2 = i. H = ii. O = f. 2C7H5(NO2)3 i. C = ii. H = iii. N = iv. O = 8. List the number of atoms of each element within the compound below. C=2 O =4 Compound Atoms in Compound Na = 1 NaCl Cl = 1 Ba = BaCl2 Cl = LiBr FeS2 Ba = BaSO4 S= CaSO4 3CaCO2 C6H4Cl2 C2H4O2 Mg(OH)2 C7H5(NO2)3 2 Ca(H2PO4)2 2HBr 3H20 2C202 O= 9. Translate the description into chemical equations a. Two molecules of ethane (C2H6) reacts with seven molecules of oxygen (O2) to form four molecules of carbon dioxide ( CO2) and six molecules of water (H2O). b. Four atoms of phosphorus (P) reacts with five molecules of oxygen (O 2) to form two molecules of diphosphorus pentoxide (P2O5).