Here are some suggestions for your notecard-
polyatomic ions you tend to forget
special reactions- HIGHLIGHT METATHESIS!
concentration formulas
gas law formulas
values for R and STP
pH & pOH formulas
reminders about how to do:
-rate law
-equilibrium
-redox
As you are working through the review, keep a sheet to write down formulas, constants, ideas & processes that you tend to forget or confuse, THEN make out your notecard from that sheet. Don't overfill the notecard. It is there as a reminder and security blanket. It doesn't help you if you can't find anything on it.
On #28 on page 1 of the review sheet, how do you convert the 210 cm^3 of Oxygen into torrs to find the partial pressure of oxygen?
ReplyDeleteThanks
Find the mole fraction of O2 (or %vol since gases at the same T&P contain the same # of molecules- Avogadro's Prin), then multiply by the total P.
ReplyDelete210/(210+780+10)= 0.21
therefore 0.21*740= 155.4 torrs
On #13 of the supplemental problems i have the Kb=(OH-)/[B] formula but don't know what to plug in? They give you that HF=2.9 x 10^-11.
ReplyDeleteThe easiest way is that Ka*Kb=1x10^-14
ReplyDelete- don't forget that Kb=(OH-) ^2 /[B]
the OH is squared
Remember that the pH problems are always easier if you have all the formulas in front of you at the same time.
ReplyDeleteOh because kw equals Ka*Kb
ReplyDeletebut im still suck on findin the Kb of F- instead of just OH-
ReplyDeleteon #9 of the first part of problems it gives the mole of two compounds and i went and found the molecules, but i looked at the answer to maybe get a clue on how to move forward and it makes no sense
ReplyDeleteOn #13- I just asked for the Kb
ReplyDeleteOn #9- did you make a chart with the amount at the start, used and at eq?
when assigning electrons into each level (spdf), when do you start filling the f? before or after d's?
ReplyDeleteis solid to gas a driving force
ReplyDeletee config- you would fill the 4d after the 6s, but I'll never have you go past Ba
ReplyDeletedecomp?
Basic answer- when something like a metal chlorate or metal carbonate decomposes, if forms a gas from a solid
More comprehensive answer- when you put a reaction into ionic form, if there is still a reaction, it will happen. in the decomps above, neither the solid nor the molecular gas (O2 and CO2) will break up or cancel out.
On number 49 of the review problems it says what quantity of sulfur dioxide is produce when 245 grams of sulfuric acid reacts with zinc
ReplyDeleteWouldn't this reaction produce zinc sulfate and hydrogen?
Technically that is a redox reaction similar to the one we did in lab with copper and nitric acid. The products would be SO2, ZnS and water. I wouldn't make you do one like that on the final.
ReplyDeleteI know there is alpha, beta and gamma decay, but will we have to do the one that is in reverse or something like that i don't have my radioactive test with me.
ReplyDeleteThere's alpha & beta that look like decomposition reactions.
ReplyDeleteThere's transmutation, where a small particle is fired at a larger one.
The only other one you might be talking about is an electron capture. It is a beta decay in reverse. You won't have one like that on the final.
how do you do #33? we keep trying it different ways but we never come up with the right answer
ReplyDeleteWhat is an example of a jigsaw problem for the heat of formation? Is there one on the review/final?
ReplyDeleteWhat is an example of the heat of formation/heat of reaction using unit analysis?
ReplyDelete#33 For every 2 moles of Fe there is one mole of Fe2O3, so the molar mass of Fe2O3.
ReplyDeleteJig-saw enthalpy- I don't think there is one because its all MC
UA thermo- Given grams, you can change to moles, then use the H for a given reaction. #33 on the very last page of the review.
ohh wait, i meant #33 in the other packet
ReplyDeleteOn what page?
ReplyDeleteits on page three of the three page review
ReplyDeletehow do you do 28? the one where you have to find the partial pressure of the oxygen?
ReplyDeleteSee above for the partial P of O2- very 1st comments
ReplyDelete#33- Hf is in kJ per MOLE, so use the molar mass of C8H18 to convert and cancel moles.
will we have to be able to do problems with M1V1=M2V2? and do we have to know V1/V2= the square root of M2/M1?
ReplyDeletedilution- yes
ReplyDeleteGraham's Law- you need to be able to apply it. The heaviest moves slowest.
how do you determine if a molecule has dipole-dipole forces or london dispersion forces?
ReplyDeleteyou said we would be given a pink sheet on the exam... will it include solubility rules or will have have to memorize them?
ReplyDeleteExam sheet has a PT, enthalpy values, solubility rules, solubility chart and reactivity series
ReplyDeleteEverything has London DF/VanderWaals because of the movement of the e. If there is a difference of sharing e to make polar bonds AND the right geometry to make the molecule polar, it will have dipole forces.
Will we be given a periodic table with electronegativites listed? If not, how will we be able to determine the electronegativity of a bond?
ReplyDeleteHow do you do number 11 on the supplemental problems? Do you have to write a reaction?
ReplyDeleteThe farther apart the elements, the larger the electronegativity. Upper right has the highest, lowest left has the lowest.
ReplyDeleteAmmonia is a weak base, you need the Kb (I'd give it to you on the test) from the chart in the back of your text.
How do you do number 7 on the supplemental problems?
ReplyDeleteSo given a substance like KCN, or HBr, how would you be able to decide what kind of intermolecular force is in each of those?
ReplyDeleteBoth KCN ( K+ and CN-) and HBr are ionic, therefore dipole-dipole.
ReplyDelete#7- Ba(OH)2 is a STRONG base so it completely dissociates BUT there are 2 OH so the [OH]= 2*the molarity of Ba(OH)2.
- You have to also find the M by using the grams, molar mass and 100 mL of water.
Doesn't anyone have a name?
ReplyDeleteOn part 2 of the review problems on question 3 it says that N2O4 has a higher percentage of oxygen than NO2, why is that?
ReplyDeleteFor #16 on the supplemental review, I keep getting 7.75 x 10^-5. I am setting ka (3.0 x 10^-8)=[H+]^2/.2 M HClO. Then I'm multiplying both sides by .2 M and then taking the square roots of both sides. What am I doing wrong? The answer says 2.4 x 10^-5 M.
ReplyDelete#3 NO2 and N2O4 have the same %O, N2O and NO are definitely less.
ReplyDelete#16 Process is correct. I've searched everywhere here for a calculator that works and will do sci not and square roots with no luck. Anyone else finished that problem and have an answer?
For #16, I got the same answer as Christy
ReplyDeleteFor #16 I got the same answer as Christy did
ReplyDeleteI'm still a little confused on how to tell the shape of a molecule. i don't understand how you tell that water is in a V shape and carbon dioxide is linear, etc.
ReplyDeleteIt has to do with the way the e are put into the s & p orbitals and VESPR modeling. I would only expect you to be able to work with binary compounds on water on the final. If you take AP, you'll go into it more.
ReplyDeleteand water, not on water
ReplyDeleteon problem 52 on page 7 of the review. what is it asking for? what is titration?
ReplyDeleteRemember the last lab we did where we titrated HCl and NaOH using phenolphthalein? They are asking for the base.
ReplyDeleteIn #32 it says that a system absorbs 500J of heat from its surroundings and does 25 J of work on the surroundings. What is the change in E for the surroundings. Wouldn't it be -475 J for the surroundings because the system absorbs 500 and puts out 25? The answer says +475J
ReplyDeleteThe system would be +475 and the surroundings would be -475.
ReplyDeleteI WILL STOP ANSWERING QUESTIONS AT 11pm
ReplyDeleteI EXPECTED EVERYONE TO BE IN BED SOON AFTER THAT! You can't think if you're brain is asleep.
I'm going to try to be in the USC from about 7 until 7:30 tomorrow morning.
in the reaction N2O4 + energy <--> 2NO2, would increasing the temp shift the reaction left or right?
ReplyDeleteis energy treated like a normal reactant/product?
To the products/right
ReplyDeleteOn #32 on the multiple choice part of the nine page review, it asks what the reaction rate expression is if 2A+ B --> C is a first order reaction. Why would it be Rate= k[A]?
ReplyDeleteRemember that rate is based on experimental data not the coefficients. If it says it is 1st order, then the exponent for A is 1. If it was 2nd order, it would be rate = k [A]^2
ReplyDeletethere is a question on a previous review sheet that says: if a reaction A+2B-->C+D is second order in A and zeroth order in B, which of the following will cause the rate to double?
ReplyDeletea) double [A] and keep [B] constant
b) increase [A] by a factor of 2.5, double [B]
c)double [A], halve [B]
d) double both [A] and[B]
e) increase [A] by a factor of 1.4, double [B]
i really don't understand these questions.
rate = k [A]^2 [B]^0
ReplyDeleteSince B is 0 order, changing its concentration will have no effect on the rate.
In the options,
a- doubling will cause the rate to increase by 4
b- x2.5 will increase it by 2.5^2 or 6.25
c- same as a
d- same as a
e- 1.4^2 = 2
IT IS TIME TO GO TO BED!
ReplyDelete