Chem Lab Final Flashcards
Kinectics
study of how fast reaction rates occur
Chemical Change
one or more different properties, the original substance has been transformed to another new substance
Physical Change
Does not change any properties but the state of the sample of matter is different.
Chemical Reaction
-if a change in properties can be detected
Mass- Action Types
Combination- A+B=C
Decomposition: A-> B+C
Displacement (Single): A+BC -> B+AC
Exchange (Double Displace) : AB+CD –> AD +CB
Product- Formation Type
- Gas-Forming -gas is formed
- Precipitation - When a solid is formed in a reaction
- Oxidation-Reduction (Redox)- G.E.R, L.E.O
- Nuetralization (Acid-Base)- Acid +Base = product and H2O
- Combustion- Oxygen and Energy is a product, H20 typically a product
Solubility Rules -soluble (aq)
Group 1 and Ammonium (NH4)
Nitrates, NO3
Chlorides, Bromides, Iodides- Ex with Ag, Hg2(2+), Pb(2+)
Sulfates, SO4(2-) Except for those in Group 2
Chlorates& Perchlorates (ClO3(-) , ClO4(-)
Acetates, CH3COO(-)
Solubility Rules -insoluble (s)
all are insoluble except those of Group 1 and NH4 (Ammonium)
Phosphates, PO4(3-) ; Carbonates, CO3(2-); Hydroxides, OH(-); Oxalates, C2O4(2-); Sulfides, S(2-)
Balancing Equations
PRACTICE
wkbook or prelab activity
Balance oxygen or hydrogen, whichever one is present in the combined state. Leave until last whichever one is present in the uncombined state. 6. Check that the equation is balanced by counting the number of atoms of each element on each side of the equation.
Ionic Compounds
-have electrolytes- free ions in solution
Molecular Compounds
stays in tact- seperated but not broken, no free ions- no charge- no electricity conducted
Polyatomic Ions Ammonium NH4(+) NO(-), SO(2-), PO(3-) Hydroxide OH(-) Cyanide CN(-) Carbonate CO3(2-) Oxalate C2O4(2-)
Acetate (C2H3O2(-) or CH3COO(-) Permanganate MnO4(-) Chromate CrO4(2-) & Dichromate Cr2O4(2-) Hypochlorite CIO (-) Chlorite CIO2(-) Chlorate ClO3(-) Perchlorate ClO4(-)
Factors that influence Reaction rates (kinetics)
Concentration of reactants, temperature and the presence of a catalyst.
For a reaction to occur (Kinetics)
Reactants must collide effectively and then combine to form new substances.
-The greater the number of particles (the high the concentration) and the higher the temp. (the more rapid and more energetic the motion of the particles), the faster the reaction.
Kinetics Lab (General Idea)
To manipulate and observe the effects of temperature and concentration on reaction rates (or kinetics)
Saponification
The process of making soap.
Two main ingredients to making soap:
1) A fat or oil (i.e. Tallow or Coconut oil) TRIGLYCERIDES
2) Base so NaOH or KOH
What is the purpose of adding sat. NaCl solution to a soap solution?
The purpose is to form a precipitate, which does this by making the soap solution more polar which forces the Sodium out.
Why is ethanol added to the soap-forming reaction mixture?
The ethanol acts as the surfactant which helps the oil bond to the H2O
A byproduct is formed when prepping the soap.
Glycerol builds up during the procedure.
Why did we wash the filtered soap?
To push out the Na - Sodium leaving behind the precipitate.
Water aspirator
detach the tubing before turning off the water so that the leftover water doesn’t get sucked into the tube.
Why is soap made with Coconut Oil softer?
Because the chain of carboxylic acid is shorter making it softer.
Acid (H+ concentration
a chemical substance that neutralizes alkalis, dissolves some metals, and turns litmus red; typically, a corrosive or sour-tasting liquid of this kind.
