Chemical Reactions
How do you know a chemical reaction has taken place?
Change in physical and chemical properties
How many atoms are present in MgCO3?
5
Balance:
Na + Cl2 --> NaCl
2Na + Cl2 --> 2NaCl
What type of reaction is the following?
2H2 + O2 --> 2H2O
Synthesis
What happens to the activation energy in a reaction with catalyst?
Lowers the activation energy of a reaction so that the reaction happens more quickly.
Give an example of a diatomic molecule.
O2, N2, H2, etc.
What is the formula for carbon tetrachloride?
CCl4
Fe + O2 --> Fe2O3
4Fe + 3O2 --> 2Fe2O3
What type of reaction is the following?
2H2O --> 2H2 + O2
Decomposition
In this type of reaction, energy is released.
2Na + Cl2 --> 2NaCl + energy
exothermic
This has to happen for a chemical bond to break.
Enough energy to cause collisions with enough force to break bonds.
How many atoms of each element in 4NaOCl?
4Na, 4O, 4Cl
Mg(OH)2 + HCl --> MgCl2 + H2O
Mg(OH)2 + 2HCl --> MgCl2 + 2H2O
Name the type of reaction:
BaCN2 + H2SO4 -->BaSO4 + 2HCN
Double Displacement
How can you increase the rate of a reaction?
Increase temperature, increase concentration, increase surface area, add a catalyst
Name the 5 parts of the following equation:
2H2 + O2 --> 2H2O
coefficient subscript reactants yield product
How many atoms of each element in Fe(NO3)2?
1Fe, 2N, 6O
Balance the following equation:
Mg + N2 --> Mg3N2
3Mg + N2 --> Mg3N2
Name the type of reaction:
Zn + 2HCl --> ZnCl2 + H2
Single displacement
Photosynthesis requires energy:
6CO2 + 6H2O + energy --> C6H12O6 + O2
endothermic
Why do chemical equations have to be balanced?
Because conservation of mass means that matter cannot be created or destroyed which means that every atom must be accounted for in both the reactants and the products.
How many atoms of each element in 2Al2(CO3)3?
4Al, 6C, 18O
Ba(CN)2 + H2SO4 --> BaSO4 + HCN
Ba(CN)2 + H2SO4 --> BaSO4 + 2HCN
C6H12O6 + 6O2 -->6CO2 + 6H2O + energy (respiration) is what type of reaction?
Combustion
Preservatives and antibiotics are substances that slow down reactions and called this.
Inhibitors