1.2 Water: Life's Solvent Flashcards
-Hydrogen bonds form readily between water molecules in both liquid water and ice.
This bonding forms an arrangement known as the ________ _______
water lattice
Most molecules that are the size of water,
such as H2, O2, CO2, HCl, and H2S, are _____ at room temperature.
gases
In liquid water, the hydrogen bonds that hold the _______ together constantly break and reform, allowing water molecules to slip past one another and _______ the lattice in new positions.
This gives liquid water its ______ properties.
lattice; reform; fluid
In ice, the water lattice is a _______ crystalline structure.
rigid
Specific heat definition
Specific heat is the amount of thermal energy that is required to increase the temperature of a given quantity of water by one degree Celsius.
If the boiling point of water were −81 degrees C, most of the water on Earth would be in the _________ state
gaseous
The hydrogen bond lattice of water results in water molecules staying close together—a property called __________.
cohesion
Surface tension definition
Surface tension is the measure of how difficult it is to stretch or break the surface of a liquid
Water molecules on the surface of a body of water can form hydrogen bonds on all sides, except the side that faces the _____.
This creates an _______ in bonding, which produces a force that places the surface water molecules under _______ and makes them more resistant to separation than the molecules below the surface.
air; imbalance; tension
True or false
Surface tension is strong enough to allow small insects, such as water striders, to walk on water
true
Water molecules can also form hydrogen bonds with other polar molecules— a
property called _______.
adhesion
cohesion
water molecules form hydrogen bonds with each other
adhesion
water molecules form hydrogen bonds with other polar molecules
high specific heat capacity
hydrogen bonding causes water to absorb large amounts of thermal energy as its temp increases, or lose large amounts of thermal energy as its temp decreases
high specific heat of vaporization
Hydrogen bonding causes liquid water to
absorb large amounts of thermal energy and
become a vapour (gas).
effect of cohesion
high surface tension
effect of adhesion
capillary action and solubility of polar compounds
effect of high specific heat capacity
temp moderation
effect of high specific heat of vaporization
evaporation and cooling
effect of highest density at 4 degrees celsius
ice floats on water
water molecules are small and strongly ____
polar
The surface coat of water, called a _______ ____, reduces the ________ between the molecules or
ions of another substance and promotes their separation.
hydration shell; attraction
The hydration shell tends to prevent the
ions from ___________.
re-associating
Why do ionic substances or salts dissolve so easily in water?
Sodium chloride dissociates in water because water molecules quickly form hydration shells around the Na+ and Cl- ions of the salt crystals.
The surrounding water molecules REDUCE the attraction between ions so much that they
SEPARATE from their normal crystal lattice structure and enter the surrounding water
lattice as hydrated ions.
