Day 1 - Notes Unit: Chemical Reactions Diatomic elements, Writing formula equations from word equations
After today you will be able to… • Name the diatomic elements • Write formula equations given the word equation for a chemical reaction heat Pt
A chemical equation represents a chemical reaction. ReactantsProducts “Yield” • Reactants and products are separated from each other with a plus (+)sign.
Common forms of chemical reactions… A + B C A B + C A + B C + D
Chemical equations can be written as word equations or formula equations. Formula equations can be balanced or unbalanced.
Word Equation: Iron + Oxygen Iron (III) Oxide Formula Equation: 4Fe(s) + 3O2(g) 2Fe2O3(s) Balanced!
Symbols in Chemical Equations heat Pt
Just write the symbol Example: “Sodium”=Na • Br2 I2 N2 Cl2 H2 O2 F2 • Have the subscript “2” Examples: “Bromine”=Br2 “Hydrogen” = H2
(nM +nM) (M +nM) • Prefixes for subscripts Examples: “dinitrogen tetraoxide” • Balance charges!!! Example: “calcium chloride” Ca+2 Cl-1 Cl-1 N2O4 CaCl2
Na+1 Cl-1 Na+1 F-1 + F2 NaF + Cl2 NaCl Examples: Convert into formula equations… 1. sodium chloride + fluorine sodium fluoride + chlorine 2. aluminum + sulfur aluminum sulfide Helpful tip: Keep all substances and + signs in line with each other! Al+3 S-2 + S Al Al2S3
Zn+2 S-2 Mg+2 (AsO4)-3 Mg+2 S-2 Zn+2 (AsO4)-3 3. zinc + magnesium zinc + magnesium sulfide arsenate arsenate sulfide + Mg3(AsO4)2 Zn3(AsO4)2 + MgS ZnS
Do now: Complete “Exit Ticket” Then: Begin WS 1 (Homework)