chapter 3 Flashcards
water
solution
homogeneous mixture of 2+ substances
solvent
dissolving agent
solute
substance that dissolves
aqueous solution
in which a solute can dissolve in water
hydration shell
sphere of water molecules around each dissolved ion
hydrophilic
substance that has an infinity for water (loves water)
hydrophobic
nonionic/nonpolar substances that repel (fear) water
what is an example of a hydrophilic agent?
cellulose in plants, helping water being distributed throughout.
what is an example of a hydrophobic solution
vegetable oil
molarity
moles per 1L of solution
what is a hydrogen ion
H+
what is an hydroxide ion
OH-
what is an hydronium ion
H30+
acid
substance that increases hydrogen ion concentration
base
substance that reduces hydrogen ion concentration
How is pH measured?
negative logarithm of hydrogen concentration
buffers
substance that minimizes changes in a concentration of H+ and OH- solutions
human blood must be within what pH
7-7.8
what do human bodies have to keep their pH normalized?
buffers
what is formed by oceans absorbing CO2
carbonic acid
ocean acidification
alters the delicate balance of life in oceans
water molecule is shaped like?
a V
a water molecule has what types of bond
single covalent polar bond
which element is the bond in water closer to?
oxygen because of oxygen having a higher electronegativity
What molecule has uneven distribution of the charges and frequently asymmetrical
polar molecule
polar covalent bond
covalent bond between atoms that differ in electronegativity
what are the 4 emergent properties of water?
cohesion of water molecules
moderation of temp
water is the solvent of life
expansion of freezing
cohesion
clinging of one substance to itself
adhesion
clinging of one substance to another
surface tension
measure of how difficult it is to stretch or break the surface of a liquid.
what does cohesion contribute to the organism’s functioning
dissolving nutrients and transportation of water
spider walking on water is a demonstration of what emergent property of water
cohesion of water molecules (surface tension)
what is moderation of temperature
water stores heat and modifies based on temp
kinetic energy
the energy of motion
thermal energy
kinetic energy associated with random movement of atoms or molecules
temperature
avg kinetic energy
heat
transfer from one body of matter to another
calorie (cal)
amount of heat it takes to raise heat temp of 1g of water by 1 degree Celsius
kilocalorie (kcal)
1000 cal for 1 kilogram of water to be raised 1 degree celsius
specific heat
amount of heat that must be absorbed for 1g of that substance to change its temp 1 C
vapor
molecules moving fast enough to overcome the attractions and depart
what is a measure of how well a substance changes temp
specific heat
heat of vaporization
quantity of heat a liquid must absorb for 1g of it to be converted from liquid to a gas
does water require high or low vaporization energy
high
water having high specific heat is due to
the hydrogen bonding
whats evaporative cooling
the liquid of vapor that is released, allows for the liquid to cool down
why can ice float on water
water is unusual and is less dense, allowing it to float
electronegativity
a chemical property that describes the ability of an atom to attract electrons towards itself
why is there a partial +/- charge
the net effect due to the difference in electronegativity
What are the cut offs on the electronegativity polarity scale
> 0.4 nonpolar
0.4-2 polar
<2 ionic
Why do He, Ne, & Ar have no electronegativity?
They have a full outer shell
How do 2 of the same atoms share a covalent bond
the 2 atoms share the bond equally
whats a nonpolar molecule
equal sharing of electrons
what’s a intermolecular bond
bond that connect several molecules together
maximum number of hydrogen bonds a water molecule can form
4
what’s a intramolecular bond
bond in between atoms in a single molecule
What molecule is usually symmetrical and has little or no partial charge
nonpolar molecule
T/F a partially (-) charged oxygen atom must be present in a hydrogen bond
false
in its liquid state, what allows water to be fragile and short lived
the hydrogen bonds due from the the polar molecules
what depends on matter’s volume, heat or temp?
heat
T/F a partially (+) charged hydrogen atom must be present in a hydrogen bond?
true
hydrogen bond
a partial positive attraction to a partial negative molecule
what doesn’t depend on matter’s volume? heat or temp?
temp
does a lukewarm pool or a steaming cup of coffee have more heat?
lukewarm pool
why can a large body of water absorb and store a great amount of heat without changing temps very much
water has a high specific heat
Why does water have a high specific heat?
due to hydrogen bonds
does a lukewarm pool or a steaming cup of coffee have a higher temp?
steaming cup of coffee
how does water moderate temperature through sweating
“hottest” molecules (with most kinetic energy) are most likely to leave as a gas, leaving behind “colder” molecules
sugar dissolves in water, what is the solute, solvent, and solution
sugar–solute
water–solvent
sweet water– solution
hydrogen shell
sphere of water molecules that surrounds solutes when they are dissolved in water
are solutes hydrophobic or hydrophilic
hydrophilic
the lower pH of a solution, the more or less acidic?
more acidic
what equation do you use to calculate the pH of a solution
= -log[H+]
whats the pH of human blood
7.4
what is responsible for making the acid in the body
parietal cell, stomach lining
increase in pH means that [H+] has
decreased
acidosis
pH in blood is less than 7.35
alkalosis
when pH in blood is more than 7.45
What is expected to happen when the blood pH is higher than normal?
Carbonic acid will disassociate to form bicarbonate and protons
