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What is 1 + 3?
The unequal sharing of electrons within a water molecule makes the water molecule _____.
The tendency of an atom to pull electrons toward itself is referred to as its _____.
what type of bond is found between the oxygen and hydrogens in water?
Water is moving up the tree as it ______ from the leaf surface.
Water molecules cling to the side of a beaker. This is an example of?
Water molecules are attracted to each other. This is an example of?
A needle floats when it is placed gently on top of water in a bucket. This is an example of?
Water molecules cling to plant cell walls. This is an example of?
A drop of water spilled on a table form a drop on the table, rather than spreading out on the surface. This is an example of?
A water strider runs across a pond without breaking the surface. This is an example of?
In a neutral solution the concentration of hydrogen ions is equal to the concentration of _____?
A water molecule that gains a hydrogen becomes a _____?
A water molecule that loses a hydrogen ion is referred to as a _____?
The transfer of a hydrogen atom from one water molecule to another is referred to as _____?
What is the charge on a hydronium ion?
What is the charge on a hydroxide ion?
About _____ molecules in a glass of water are dissociated.
1 in 500,000,000
Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?
the absorption of heat by the breaking of hydrogen bonds
The bonds that are broken when water vaporizes are?
hydrogen bonds between water molecules.
Measurements show that the pH of a particular lake is 4.0. What is the hydrogen ion concentration of the lake?
Measurements show that the pH of a particular lake is 4.0. What is the hydroxide ion concentration of the lake?
Water molecules have a polarity, which allows them to be electrically attracted to other water molecules and other polar molecules by weak chemical bonds known as _____.
Many of water's emergent properties, such as its cohesion, its high specific heat, and its high heat of vaporization, result from the fact that water molecules _____.
are electrically attracted to each other
The amount of energy that must be absorbed or lost to raise or lower the temperature of 1 g of liquid water by °C _____.
is 1 calorie
Because organisms are made primarily of water, they resist rapid temperature changes. This useful quality is based on water's _________.
high specific heat
Sodas typically contain sugar, flavorings, coloring agents, and carbon dioxide dissolved in water. The best term to describe this mixture would be _____.
an aqueous solution
If the molecular mass of a carbon atom is 12, the mass of a hydrogen atom is 1, and the mass of an oxygen atom is 16 daltons, how many molecules does one mole of sugar (C12H22O11) contain?
6.02 x 10^23
An acid is a substance that _____.
increases the hydrogen ion concentration of an aqueous solution
A pH of 6 is how many times more acidic than a pH of 9?
A _____ accepts hydrogen ions when they are in excess and donates hydrogen ions when they have been depleted.
Most acid precipitation results from the combination of ____ with water in the atmosphere, forming strong acids that fall with rain or snow.
sulfur oxides and nitrogen oxides
We can be sure that a mole of table sugar and a mole of vitamin C are equal in their?
number of molecules
List four characteristics of water that are emergent properties resulting from hydrogen bonding.
cohesion/adhesion, moderation of temperature, insulation, universal solvent
Hydrogen bonds hold water together
the clinging of one substance to another
movement of molecules, faster the movement, heat increases
measure of heat intensity, average kinetic energy
Coastal climates have milder climates than adjacent inland areas. This is an example of what property of water?
Ocean temperatures fluctuate much less than air temperatures on land. This is an example of what property of water?
Ice floats on water. This is an example of what property of water?
Humans sweat and dogs pant to cool themselves on hot days. This is an example of what property of water?
Define the term solute.
the result of a solvent, h2o + dissolved substance
Define the term solvent.
the dissolving agent of a solution
Define the term solution.
a liquid that is a completely homogeneous mixture of 2 or more substances
Define the term hydrophobic.
does not absorb
Define the term hydrophillic.
absorbs water, loves water
What are the products in the dissociation of water?
hydronium ions (H30+) and hydroxide ions (OH-)
What is the concentration of the products of dissociation in pure water?
at 25 degrees C = 1x10^-7 M each
Define the term acid.
a substance that increases the hydrogen ion concentration of a solution
Define the term base.
a substance that increases the hydroxide ion concentration of a solution
Define the term pH.
the negative logarithm (base 10) of the hydrogen ion (H+) concentration of a solution
How do acids and bases alter the hydrogen ion concentration of a solution?
Adding H+ will make a solution more acidic. Decreasing H+ will make a solution more basic.
How do buffers work? Use the bicarbonate buffer system to explain.
1. Carbonic acid and bicarbonate act as a pH regulator. 2. If H+ is depleted (pH rises) more carbonic acid dissociates. 3. If H+ is in excess the bicarbonate acts as a base. 4. Removes excess H+ ions.