Reading Equations
What does a triangle over the arrow represent in an equation?
Heat
When a compound breaks apart into simpler substances
Decomposition
CH4 + O2 -->
CH4 + 2O2 --> CO2 + 2H2O
Combustion (methane)
Finish & balance:
a) Cu+2 + O2 -->
b) reaction type?
a) 2Cu+2 + O2 --> 2CuO
b) synthesis (S)
List the 7 diatoms (100 each)
H, N, F, O, I, Cl, Br
DAILY DOUBLE!
1) Which of these would you never see in an equation?
F 2F F2 2F2
2) Why? Best answer gets the bonus points & shot!
1) would not see F or 2F
2) fluorine is very reactive and is always in a compound. Both F and 2F represent individual atoms of fluorine (which don't exist in nature)
When a single type of element replaces a similar type of element in a compound
Single replacement
Al + O2 --> ???
4Al + 3O2 --> 2Al2O3
Synthesis (metal w/ oxygen)
Finish & balance:
a) PtO -(heat)->
b) reaction type?
a) 2PtO -(heat)-> 2Pt + O2
b) decomposition (D)
The law that we are satisfying by balancing equations
Law of Conservation of Mass
DAILY DOUBLE!
1) How many of each element (C, H, and O) are to the left (or right) of the arrow?
C6H12O6 + 6 O2 --> 6 CO2 + 6 H2O
2) What is the term for this reaction in living things?
1) 6 carbon, 12 hydrogen, 18 oxygen
2) cellular respiration (breaking down glucose for ATP)
When two or more simple substances combine to form a single compound
Ca + HCl -->
Ca + 2 HCl --> H2 + CaCl2
Single replacement of hydrogen in acid by a metal
Finish & balance:
a) K + NaCl -->
a) K + NaCl --> Na + KCl
b) single replacement (SR)
The term for a solid substance that is dissolved in water to allow it to react
aqueous (aq)
DAILY DOUBLE!
2 NH3 -(heat)-> N2 + 3 H2
1) How many hydrogen ATOMS are to the right of the arrow in the equation?
2) How many hydrogen MOLECULES are to the right of the arrow in the equation?
3 H2
1) 6 hydrogen ATOMS
2) 3 hydrogen MOLECULES
When a hydrocarbon burns
Combustion
Finish & Balance:
a) K2CO3 -(heat)->
b) reaction type?
a) K2CO3 -(heat)-> K2O + CO2
b) Decomposition (D)
Finish & balance the one that will react:
a) Cl2 + LiBr -->
b) I2 + LiBr -->
a) Cl2 + 2 LiBr --> Br2 + 2 LiCl
chlorine is higher than bromine (nonmetals) so it will replace it
The whole numbers placed in front of substances in equations to balance them
Coefficients
Complete and balance the equation:
C9H18 + O2 -->
2 C9H18 + 27 O2 --> 18 CO2 + 18 H2O
When two compounds exchange ions to make new compounds
Double replacement
Finish & balance:
a) silver acetate + tin (IV) nitride
b) reaction type?
a) 12AgNO3 + Sn3N4 -> 4Ag3N + 3Sn(NO3)4
b) double replacement (DR)
Finish & balance:
a) HNS + oxygen
b) Reaction type?
a) 4HNS + 5O2 -> 2H2O + 2N2 + 4SO2
b) combustion (C)
Term for a chemical that speeds up a reaction
Catalyst