1. Chemical Reactions and Gases

2. 4 TYPES OF CHEMICAL REACTIONS
Synthesis Reaction
Decomposition Reaction
Single Displacement Reaction
Double Displacement Reaction

3. SYNTHESIS REACTION = is one in which a single product is produced from two or more reactants. X + Y  XY Examples: H2 + Cl2  2HCl S + O2  SO SO3 + H2O  H2SO NO + O2  2NO2

4. DECOMPOSITION REACTION = is one in which a single reactant is converted into two or more simpler substances.
XY  X + Y
Examples: 2CuO  2Cu + O2
2H2O  2H2 + O2
CaCO3  CaO + CO2

5. SINGLE DISPLACEMENT REACTION = is one in which one element of a compound is replaced by another element. X + YZ  Y + XZ Examples: Zn + H2SO4  H2 + ZnSO4   Ni + 2HCl  H2 + NiCl2   Mg + Ni(NO3)2  Ni + Mg(NO3)2  

6. DOUBLE DISPLACEMENT REACTIONS = is one in which two compounds exchange parts with each other to form two different compounds.
AX + BY  AY + BX
Examples: NaOH + HCl  NaCl + HOH
  AgNO3 + NaCl  NaNO3 + AgCl
  NaF + HCl  NaCl + HF

7. How do you know that a chemical reaction has occurred
How do you know that a chemical reaction has occurred? What should you look for?
Change in color
Precipitate forms
Change in temperature
Effervescence occurs

8. Exothermic Chemical Reaction: Occurs when the chemical reaction releases heat. Products become warmer than the reactants.

9. Endothermic Chemical reaction: A chemical reaction where energy is absorbed. The products temperature is colder than the reactants.

10. Chemical Gases

11. Carbon Dioxide (CO2): A colorless odorless gas that does not aid in combustion. A burning flame will go out.

12. Oxygen (O2): A colorless, odorless gas that will make a flame burn brighter and faster. Has the capability of making a burning ember burst back into a flame. A gas which is required for combustion to occur.

13. Acetylene(C2H2): A colorless gas that will burn when oxygen is present.

14. Hydrogen(H2): A colorless gas that will explode in the presence of fire or a spark if oxygen is present too.