L4 CHEM - STRUCTURE AND PROPERTIES OF WATER Flashcards
makes up a large proportion of the entire biosphere and of these, 97.5 % is saltwater and the remaining 2.5 % is freshwater.
WATER
is locked up in ice and glaciers, deep and shallow underground lakes, soil, atmosphere, and in the rivers.
WATER
The human body consist of
50-75% water.
the UNIVERSAL SOLVENT because it dissolves more substances than any other liquids.
WATER
2 Structure of water
- Water is POLAR because of the unequal sharing of electrons gives the water molecule a slight NEGATIVE charge near its oxygen atom and a slight POSITIVE charge near its hydrogen atoms.
- Water’s unique properties result from the strong intermolecular forces of attraction characterized by the hydrogen bond.
The ____________________________ of water is a consequence of its strong IMFA caused by the formation of the H-bond. It also, explains why water is liquid at room temperature.
High Boiling Point
Refers to the amount of heat needed to change the temperature of 1 gram of a substance by 1oC.
HIGH SPECIFIC HEAT
For water, its specific heat is
1cal/g oC.
also the property of water that helps to moderate earth’s temperature.
SPECIFIC HEAT
also the reason why water balloon do NOT pop while held over a flame.
SPECIFIC HEAT
is the only substance that expands when cooled.
WATER
- For most substances, their solid form is denser than their liquid form.
- This is because the H-bond is more extensive in its solid state (ice) than in its liquid state.
TRUE
The hydrogen bond formation among water molecules causes water to have
high surface tension.
Large amount of heat is needed to vaporize a given amount of water. This causes a significant drop in temperature during evaporation.
* This explains why perspiration lowers the body temperature.
HIGH HEAT OF VAPORIZATION
