2. intro to functional groups. water: a special molecule the solvent in cells, tissues and organs is...

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2. Intro to Functional Groups

Water: A special moleculeThe solvent in cells, tissues and organs is water. Four special properties of water are:1. Hydrogen bondingEffects: cohesion, adhesion, surface

tension. More energy is needed to break hydrogen bonds than other intermolecular bonds, which gives water a high specific heat capacity.

2. DensityEffects: Ice is the only solid that floats in its

liquid! This insulates water under ice.

Water: A special molecule

3. Polar nature of the bondEffects: as a solvent, water allows polar

molecules and ionic compounds to dissolve due to water’s polarity.

4. Dissociation of intramolecular bondsEffects: 1 in 107 water molecules dissociates

to form H+ and OH- ions. This is a pH of 7 = NEUTRAL.

Functional Groups• Functional groups are parts of larger

molecules. • They greatly influence biological

reactivity because they have negative or positive regions that react to form bonds.

Draw the structural formula.

Draw the structural formula.

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