Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
45 Cards in this Set
- Front
- Back
Polar molecule
|
opposite ends of the molecule have opposite charges (one example is the water molecule
|
|
Cohesion
|
the phenomenon in which hydrogen bonds hold water together
|
|
Adhesion
|
the clinging of one substance to another
|
|
Surface tension
|
a measure of how difficult it is to stretch or break the surface of a liquid.
|
|
What has kinetic energy?
|
anything that moves
|
|
What is heat a measure of?
|
the total quantity of kinetic energy due to molecular motion in a body of water
|
|
What does temperature measure?
|
the intensity of heat due to the average kinetic energy of the molecules
|
|
Calorie
|
the amount of heat energy it takes to raise the temperature of 1 gram of water by one degree Celsius
|
|
Kilocalorie
|
the quantity of heat required to raise the temperature of 1 kilogram of water by one degree Celsius.
|
|
Joule
|
measurement of heat needed to raise the temperature of a unit of water0.239 calories, calorie= 4.184 J
|
|
Specific heat
|
the amount of heat that must be absorbed or lost for 1 gram of that substance to change its temperature by 1 degree C. can be thought of as how well an object resists changing its temperature. It changes a lot when it does change.
|
|
Heat of vaporization
|
the quantity of heat a liquid must absorb for one gram of it to be converted from eh liquid to gaseous state
|
|
Evaporative cooling
|
as a liquid evaporates the surface of the liquid that remains behind cools down
|
|
Solution
|
a liquid that is a completely homogeneous mixture of two or more substances
|
|
Solvent
|
the dissolving agent of a solution
|
|
Solute
|
the dissolved substance in a solution
|
|
Aqueous solution
|
a solution wherein water is the solvent
|
|
Hydration shell
|
sphere of water molecules around each dissolved ion
|
|
Hydrophilic
|
any substance, whether ionic or polar that has an affinity for water even if it does not dissolve
|
|
Hydrophobic
|
substances that are non-ionic and non-polar seem to repel water.
|
|
Mole
|
equal in number to the molecular weight of a substance but upscaled from Daltons to units of grams
|
|
Molecular weight
|
the sum of the weights of all the atoms in a molecule
|
|
Molarity
|
the number of moles of solute per liter of solution
|
|
Hydrogen ion
|
a single proton with a charge of +1 because the hydrogen bond shifts
|
|
Hydroxide ion
|
a water molecule that lost a proton when the hydrogen bond shifts. Has a charge of –1
|
|
Acid
|
a substance that increases the hydrogen ion concentration of a solution.
|
|
Acidic solution
|
when a solution has more H+ than OH-
|
|
Base
|
a substance that reduces the hydrogen ion concentration of a solution
|
|
Basic solution
|
when a solution has more OH- than H+
|
|
Buffers
|
substances that minimize changes in the concentration of H+ and OH- in a solutions
|
|
Acidic precipitation
|
rain, snow or fog that is more acidic than pH 5.6
|
|
Between oxygen and hydrogen which is more electronegative?
|
oxygen
|
|
What happens because oxygen is more electronegative?
|
oxygen has a slightly negative charge and hydrogen has a slightly positive charge
|
|
How many hydrogen bonds can each water molecule make?
|
4 bonds
|
|
What is behind all of water’s special properties?
|
hydrogen bonding
|
|
Why does water have more structure than other liquids?
|
hydrogen bonds are weak but they reform very quickly in liquid water
|
|
What is an example of adhesion?
|
water clings to vessels of a plant to help it move up to the leaves against gravity or a meniscus in a graduated cylinder
|
|
What is an example of cohesion?
|
molecules create a constant stream of water inside a plant to move it from the roots to the leaves.
|
|
Why is there surface tension?
|
at the surface between water and air, hydrogen bonds hold water molecules to each other and to the molecules below them. This makes the surface of water act like it has a special invisible coating.
|
|
What is an example of surface tension?
|
rock skipping, lizards walking on water
|
|
What is an example of the difference between heat and temperature?
|
a swimmer has higher temperature than the ocean but the ocean has more heat
|
|
Is it hard to convert water from a liquid to a gas? Why?
|
yes, because the many hydrogen bonds need to be broken in order for that to happen
|
|
What are the three steps in the hydrogen bond cycle?
|
1. hydrogen bonds are formed in water 2. they are broken by heat 3. they are reformed when the water cools again
|
|
What is an example of the hydrogen bond cycle?
|
when you boil water, you are adding heat to the water to break the bonds and change the water to steam. When you put your hands over the steam you feel heat and get wet as the bonds are reformed and the state changes back to water.
|
|
How does water stabilize temperature?
|
water absorbs heat from warmer air, and releases hat to cooler air. Ocean temperatures are stable for marine life. Organisms resist changes in their bodies due to high water content.
|