Download Chemical Equations - Solon City Schools

Chemical Equations
Parts of an equation and how to
balance
Chemical Equation:
Set of directions for a chemical
reaction.
The directions tell us:
1. What materials to use
2. How much you need
3. Amount of product you will get
Chemical Equations
Give info about:
 Reactants – substances being used in
the reaction (starting materials on Left
side of equation)
 Products – new substances formed
(ending materials on Right side of
equation)
*
Numbers in Equations
 Coefficients – small whole numbers in
front of compounds
ex. 2 NaCl = 2 NaCl ’s
 Subscripts – small numbers following
elements
ex. H2O = 2 H’s , 1 O
*
Indications of a Chemical
Reaction
1. Color
2. Gas / Bubbles
3. Precipitate
4. Temperature Change
5. Light
Chemists Get Practice Trying Labs
(Typically, more than one will be seen)
*
Diatomic Elements
*
 Two elements that exist bonded together
when not bonded to another elements
 Remember the seven + one rule that
starts at element #7
H
N, O, F
Cl
Br
I
At
Chemical Equation Symbols *
Symbol
(s)
(l)
(g)
(aq)
Meaning
solid
liquid
gas
aqueous
dissolved in
water
Chemical Equation Symbols *
(Cont.)
Symbol
3500
Meaning
yields
equilibrium
heated
temp at which
reaction is run
Balancing Equations
1. Check for diatomics
2. Balance metals
3. Balance nonmetals
4. Balance Oxygen
5. Balance Hydrogen
6. Recount all atoms
7. If every coefficient will reduce, write in
simplest whole number ratio