Chapters 4 and 5 Flashcards
for quiz/test
What are the first 3 gas laws? What are the equations?
Boyle’s Law, Charles’ Law, and Avogadro’s Law. P1V1 = P2V2; v1/t1=v2/t2; v1/n1=v2/n2
What is a barometer? Who invented it? How?
A device for measuring pressure in Torr. Evangelista Torricelli. He filled a glass tube with Hg and inverted it into a dish. At sea level, the height was 760mm.
What is a manometer?
Measures pressure of gas in a container.
How do you measure the pressure of a gas using a barometer?
pressure in air - pressure in barometer with gas
How many mmHg (torr) are in 1 atmosphere?
760
atm to Psi?
14.69
What is STP?
0C (273.15K) and 1 atm
What is the molar volume of an ideal gas?
22.41L
What is the ideal gas law? Units?
PV = nRT…. P: pressure (atm) ; V: volume (L) ; n: moles; T: temp (K); R: 0.08206 (L * atm)/(mol * K)
What is an ideal gas?
a gas that obeys boyle;s law
Ideal Gas Law problem
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Dalton’s Law of partial pressure
Ptotal = P1+P2+P3+…
What is a mole fraction?
the ratio of the number of moles of a given component to the total # of moles in the mixture
What is vapor pressure?
the pressure of a vapor over a liquid at equilibrium
Vapor pressure/partial pressure practice problem
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Kinetic Molecular Theory’s postulates?
4 postulates:
1. particles are so small and far apart that the volume of molecules is negligible
2. particles are in constant motion, pressure is caused by these particles hitting the walls of the container
3. particles are assumed to have 0 intermolecular forces
4. the average kinetic energy of a collection gas particles is assumed to be directly proportionate to kelvin temp
REAL GASES DO NOT FOLLOW THESE ASSUMTIONS
Equation for average kinetic energy of molecules
(KE)avg = 3/2(RT), R = 8.3145 J/(molk)
units of a J?
kg*m^2/s^2
Root mean square velocity?
sqrt(3RT/m) where m is the molar mass in Kgs!!!
Root Mean Square and Average KE problems
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Gas stoichiometry practice problems in notes
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Finding empirical and molecular formulas with gases problems
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What 2 conditions does the ideal gas law describe the behavior of a gas more accurately in?
high pressure and low temp
Real Gas Law
Pobs = [(nRT)/(V-nb)] - a(n/v)^2 where b is the size of a molecule, and a is a measure of interparticle force of attraction
Real Gas Law Problem
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What does like dissolves like mean?
polar substances dissolve polar substances and nonpolar substances dissolve nonpolar substances
What is an electrolyte?
a material that when dissolved in water gives a conductive solutio
strong electrolytes?
completely ionize when dissolved in water. Soluble salts, strong acids and strong bases are usually strong electrolytes
Arrhenius definition of an acid?
produces H+ ions when dissolved in water
2 types of acids?
monoprotic (1 acidic proton) and diprotic (2 acidic protons) HCl is a monoprotic and H2SO4 is a diprotic
Arrhenius definition of a strong base?
releases OH- ions when dissolved in water. NaOH and KOH are examples
Flaw of arrhenius definition
some acids/bases are what they are even though they dont release H+ or OH-
Weak electrolytes?
ionizes to a small extent in H20. Acetic acid is a weak acid and electrolyte because only about 1% of the molecules ionize
Strong Acids/Bases I have to memorize:
Acids:
HCl, HBr, HI, HClO3, HClO4, HNO3, H2SO4 (hydrochloric, hydrochloric, hydroiodic, chloric, perchloric, nitric, and sulfuric acids)
Bases:
Group 1A metal hydroxides (LiOH, KOH, etc)
Heavy group 2A metal hydroxides Ca(OH)2, etc.
Solubility rules
- Most Nitrate (NO3-) salts are soluble
- Most salts with alkali metal ions (Li+, Na+) and ammonium ions (NH4+) are soluble
- Most Chloride, bromide, and iodide salts are soluble. Exceptions are salts with Ag+, Pb+, and Hg2+.
- Most sulfate (SO32-) salts are soluble except for those with Ba, Pb, Hg, and Ca
- Most hydroxides are slightly soluble except for NaOH and KOH
- Most Sulfide (S2-), carbonate (CO32-), chromate (CrO42-) and Phosphate (PO43-) salts are slightly soluble, except for those with conditions in rule 2
Insoluble vs slightly solube
mean the same thing
What are precipitation reactions
when two solutions are mixed and form an insoluble substance.
Know molecular equations, complete ionic equations, and net ionic equations for reactions in aqueous solutions
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Practice reactions for precipitation reactions and balancing the equations
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what is a limiting reagent?
In AP Chemistry, a “limiting reagent” refers to the reactant in a chemical reaction that is completely consumed first, thereby restricting the amount of product that can be formed, essentially acting as the “bottleneck” in the reaction; once the limiting reagent is used up, the reaction cannot proceed further, regardless of how much of the other reactants remain.
What is a dilute?
a small amount of solute is dissolved in a solution at a given temperature
What is molarity?
moles of solute per volume of solution in liters
what does M mean?
moles of solute/Liters of solution
what does 1.00M mean?
1 mole of solute per liter of solution
what is a standard solution?
a solution whose concentration is accurately known
Practice calculating molarity
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What is dilution?
water is added to a concentrated solution to get desired molarity
what is a stock solution?
concentrated form of a solution which has a known molarity; this is usually purchased
What is the equation for dilution?
M1V1 = M2V2
Describe how you would prepare 1.0L of 0.10M NaCl from a 2.5M NaCl stock solution
2.5M*V1 = 0.1M * 1L
V1 = (0.1M*1L)/(2.5M) = 40ml
Use 40ml of stock solution and dilute w/ water until you reach one liter (reach v2)
Stoichiometry of solutions practice
60, 62, 65, and 66 in txt book (last one rlly good)
What is the Brownstead-Lowry definition of bases and acids?
an acid is a proton donor and a base is a proton accepter
remember arrhenius definition?
acid: H+
base: OH-
What is the lewis definition of acids and bases?
acid: e- acceptor
base: e- donor
What is the form of an acid/base reaction?
Acid + Base -> salt +H2O + gas (in some cases)
acid/base rxn practice
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What is titration?
the addition of a measured volume of base of known concentrate (Called the titrate) into an acid solution to be analyzed (analyte)
What is volumetric analysis in titration?
used to determine amount of analyte
What is the equivalence/stoichiometric point?
the point in the titration where enough titrant has been added to react exactly with the analyte. To indicate this point we use an indicator.
What is an indicator in titration?
a color-changing chemical used to mark endpoint of a reaction. In class we used phenolphthalein which is colorless when acidic and pink when basic. When even the 1st drop of excess base is added the solution will turn pink and the endpoint will have been reached.
What is the endpoint in a titration?
around 1 drop of base past equivalence point
what volume of 0.100M NaOH will react completely with 25.00ml of 0.200M HCl
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titration problem practice
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What are redox reactions?
oxidation-reduction reactions are when one or more e- are transferred. Oxidation is losing an electron, reduction is gaining. Oxidation can also be gaining an oxygen or losing a hydrogen.
what is the oxidative number/state?
provides a way to keep track of e- and verify e- transfer
Rules for assigning oxidation states:
Format: summary: examples;
an element in element form is 0: Na, O2, Hg;
a monoatomic ion is the charge of the ion: Na+, Cl-;
Fluorine is -1: HF, PF3;
Oxygen is -2 with exception of O2^2- in which it is -1: H20, CO2;
Hydrogen is +1 in covalent compounds: H20, HCl, NH3
Way to remember the rules: Eat my fuckin ovaries hoe (element, mono-atomics, fluorine, oxygen, hydrogen)
Practice assigning oxidative states
examples:
1. CH4
2.ZnCl2
3.O3
4.HNO3
- each H is +1 so C is -4
- Cl has a -1, so Zn is +2
- 0 because it is bonded to itself (rule 1)
- O is -2, H is +1, so N has to be +5!
do more if needed
