Smells, Tastes & Functional Groups!. 1. Functional Groups: are structural features that show up repeatedly in molecules and seem to account for some of their chemical properties (ex: smell). What are the main functional groups?. KETONE (carbon double-bonded to an oxygen).
1. Functional Groups: are structural features that show up repeatedly in molecules and seem to account for some of their chemical properties(ex: smell).
(carbon double-bonded to an oxygen)
(carbon double-bonded to an oxygen & attached to another oxygen atom which is attached to another carbon)
(carbon double-bonded to an oxygen & attached to another oxygen atom which is attached to a hydrogen)
(carbon bonded to a nitrogen atom)
(carbon bonded to an oxygen bonded to a hydrogen atom)
Structural Formula: A drawing or diagram that a chemist uses to show how the atoms in a molecule are connected. It is a 2D picture of the molecule. Structural formulas show how the atoms in a molecule are put together. #3 on this page shows _____ (how many?) structural formulas.
Molecular Formula: The shorthand notation a chemist uses to show how many atoms of each element are present in a particular molecule or the ratio of ions in an ionic formula. Ex: H2O
6. Bond: A connection between atoms in a molecule. In structural formulas, the covalent bonds are represented as _______________. Double bond = 2 lines together. How many lines would you need for a triple bond? ______.
We saw this in the smell lab—2 substances had the formula C4H8O2 but one smelled putrid & the other smelled sweet!
**Question to ponder: Can molecules have the same molecular formula and smell differently? Answer: _________
A. Examine the following molecules. What patterns do you see in the bonding of hydrogen, oxygen, carbon & nitrogen?
Vial K—Fishy, diisobutylamine Vial E—Minty, menthone
a. How many bonds (lines) do carbons always have around them? ___ b. How about nitrogen atoms? ___ c. How about hydrogen atoms? ___ d. How about oxygen atoms? ___
H = 1 bond
O = 2 bonds
N = 3 bonds
C = 4 bonds
(H-1) (O-2) (N-3) (C-4)
***Tip: things that can form more bonds are more likely to show up in the middle of the structure***
D. Draw each of the following molecules:
E. Draw C4H10 correctly, but in two different ways!