Presentation on theme: "Alkanes vs. Alkenes A Stinky Lab Turned into an Un- Stinky Power Point Presentation."— Presentation transcript:
Alkanes vs. Alkenes A Stinky Lab Turned into an Un- Stinky Power Point Presentation
What do you think these words mean? Homologous Series Saturated Hydrocarbons Unsaturated Hydrocarbons A group of compounds whose chemical formula increases by one carbon atom from one compound in the series to the next Ex: CH 4, C 2 H 6, C 3 H 8 … Hydrocarbons with all single bonds, any alkanes Hydrocarbons without all single bonds, any alkenes or alkynes
Melting and Boiling Point Look at the regular Chem text page 753 What pattern do you see in boiling point as alkanes get more carbons? What pattern do you see as molecules get less saturated? More carbons = higher boiling point Less saturated = more double bonds = lower boiling point… mostly
Melting Point cont. Put these in order of increasing melting point: EthaneOctaneButane1-Octene EthaneOctaneButane1-Octene EthaneButane 1-Octene Octane Ethane < Butane < 1-Octene < Octane
Water with green food color Solubility Alkane Alkene Summary: Alkanes and Alkenes are both NOT soluble in water. Plus, they are less dense than water.
Combustion Alkane Alkene Blue Flame Black Smoke Summary: Alkanes burn cleaner than Alkenes
Alkane Alkene Alkane Alkene is called cracking Alkene Alkane is called addition C 3 H 8 heat and Ni catalyst C 3 H 6 + H 2 C 2 H 6 + H 2 C 2 H 8
Identifying Alkanes/enes Alkane + Halogen Haloalkane (slow), substitution Alkene + Halogen Haloalkane (fast) this is called addition C 3 H 8 + Br 2 C 3 H 7 Br + HBr C 2 H 4 + Br 2 C 2 H 4 Br 2
Quick Review Alkanes and alkenes are ____ soluble in water As # of C increases, melting point ____ As saturation decreases, melting point ____ Combustion of _____ is cleaner than _____ Alkanes change into alkenes with _____ and _____ Alkenes turn into alkanes with _____ An ____ reacts quickly to decolorize Br 2 NOT increases decreases heat Nickel catalyst alkanesalkenes hydrogen alkene
Who Cares? You! People in developed countries eat an average of 88 pounds of fat a year Are you eating the right ones for your health?
We need fat in our diet To… Absorb shock, warmth, energy, move electrical/nerve currents, construct membranes, brain function, sex glands, hormone function Cholesterol too Can be from food, but our body makes all we need Hormones, steroids, skin protectant, antioxidant “Good cholesterol”= HDL, “Bad” = LDL
Saturated Fats Animal products + coconut and palm oils, peanuts, butter Solids at room temperature and body temperature Can stack up on each other because the structures are floppy, even form crystal structures (aggregate) Insoluble in water What they can do that’s bad: Deposit + hardens arteries and increases blood pressure Blood clots Increase bad (LDL) cholesterol Avoid Them!
Butter This shows the result when different brands of butter and margarine are combined with bromine. Which brand has the most saturated fat? Which has the least? Most saturated Least saturated So… Gold’N Canola is the worst for you and Flora Olive is the best!
Oils This shows the result when different butters and oils are combined with bromine. Which brand has the most saturated fat? Which has the least? So… Coconut oil is the worst and Wesson “best blend” is the best Most Sat Fat Most Unsat. Fat
Unsaturated Fats Have a very slight + and – charge, so they repel each other, keeping them fluid (liquid at room and body temperature) and unable to aggregate like saturated fats Less stable (more likely to oxidize, turn rancid) than saturated fats From 1 to 6 double bonds What they can do to your body… Monounsaturated Decrease bad cholesterol and increase good Olive oil, canola oil, avocado, nuts, butter Polyunsaturated Decrease the bad Omega fatty acids increase brain function Cold water fish, almonds, walnuts, leafy veggies, flax, hemp, safflower, + brains, eyes, and testes of animals (which is why those parts were prized by primitive hunter-gatherer people)
Cis vs. Trans A decent video
Trans Fats Artificially created unsaturated fat, “partially hydrogenated” changes a cis double bond into a trans Much more stable than unsaturated fats, but still just as cheap Margarine, shortening, fried food, packaged food Why are they bad? They are solids Clots and artery blockage Cancers Interfere with electrical currents Avoid Them!
Extra Links Human body cross section: http://www.madsci.org/~lynn/VH/transverse.ht ml http://www.madsci.org/~lynn/VH/transverse.ht ml http://www.madsci.org/~lynn/VH/transverse.ht ml http://visiblehuman.epfl.ch/intapplet.php http://visiblehuman.epfl.ch/intapplet.php http://www.uchsc.edu/sm/chs/browse/browse. htm