Chem Props of Water

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Forms of Water

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Water consists of an Water is a Polar Molecule oxygen atom bound to
-has oppositely charged two hydrogen atoms ends by two single covalent bonds. – Oxygen has unpaired & paired electrons which gives it a slightly negative charge while Hydrogen has no unpaired electrons and shares all others with
Oxygen
– Leaves molecule with positively and negative charged
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ends

Water molecules form Hydrogen bonds slightly positive charge hydrogen bond between (+) and (-) areas of different water molecules slightly negative charge 4

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Water’s Properties
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Cohesion
Adhesion
Capillarity
High Specific Heat
High Heat of Vaporization
Solid water (ice) is less dense than liquid
Solvent
Transparency
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Cohesion
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Cohesion refers to attraction to other water molecules.
 responsible for surface tension

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Adhesion
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Adhesion refers to attraction to other substances.
 Water is adhesive to any substance with which it can form hydrogen bonds.
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Capillary action

water evaporates from leaves = transpiration

adhesion, cohesion and capillary action

water taken up by roots 8

•trees have specialized structures to transport water: xylem and phloem plumbing.

• water molecules are dragged from the roots to the top of the tree by capillary action and cohesion: hydrogen bonds help water molecules to each other.
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High Specific Heat
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High specific heat
 Amount of heat that must be absorbed or expended to change the temperature of 1g of a substance 1o C.

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Impact of water’s high specific heat ranges from the level of the whole environment of Earth to that of individual organisms.
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A large body of water can absorb a large amount of heat from the sun in daytime and during the summer, while warming only a few degrees.
At night and during the winter, the warm water will warm cooler