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Questions (15)
camphor melts at 179.8 degrees, and it has a particularly high freezing point depression constant.(kf=40 degrees/m). when 0.186g
6 answers
3,632 views
the vapour pressure of pure water at 110 degrees is 142.7kpa. a solution of ethylene glycol and water has a vapour pressure of
4 answers
1,044 views
this is a text book question that i cannot figure out.
the decomposition of dimethyl ether at 510 degrees is a first-order
2 answers
858 views
Dinitrogen tetraoxide, N2O4, decomposes to nitrogen dioxide, NO2, in a first-order process.
If k = 2.5 x 103 s-1 at -5° Cand k =
2 answers
1,337 views
The rate constant for a reaction is 4.65 L mol-1s-1. The overall order of the reaction is:
zero first second third I am having
4 answers
4,043 views
Determine the equilibrium constant, Keq, for the reaction
5.3 10–19 18.30 1.7 1054 1.9 1018 5.7 10–55 i have tried this but
3 answers
502 views
Given a cell based on the spontaneous reaction
2AgCl(s) + Zn(s) ® 2Ag(s) + 2Cl– + Zn2+ If the zinc ion concentration is kept
4 answers
1,685 views
Given a cell based on the spontaneous reaction
2AgCl(s) + Zn(s) ® 2Ag(s) + 2Cl– + Zn2+ If the zinc ion concentration is kept
2 answers
561 views
Complete and balance the following redox equation. The sum of the coefficients when they are all whole numbers is
MnO4- + H+ +
4 answers
1,413 views
Determine the equilibrium constant, Keq, for the reaction
5.3 10–19 18.30 1.7 1054 1.9 1018 5.7 10–55 this is an assignment
5 answers
508 views
A cell can be prepared from copper and tin. What is the E° cellfor the cell that forms from the following half reactions?
Cu2+(a
7 answers
5,724 views
Complete and balance the following equations using the method of half-reaction. both reactions happen in acidic solutions:
a.
4 answers
2,159 views
Given a cell based on the spontaneous reaction
2AgCl(s) + Zn(s) ® 2Ag(s) + 2Cl– + Zn2+ If the zinc ion concentration is kept
3 answers
747 views
Given the following standard reduction potentials in acid solution:
MnO4- + 8 H+ + 5 e-® Mn+2 + 4 H2O E°cell = 1.51 V Co+2 + 2
3 answers
1,170 views
A certain vinegar is 6.02% acetic acid (HC2H3O2) by mass. How many grams of HC2H3O2 are contained in a 355-mL bottle of vinegar?
4 answers
3,228 views
Answers (14)
so doing it your way you then habe to times it by 1000 to get it back to g/mol.
what i have done is: 179.8-176.7/40 = 3.1/40 = 0.0775mol then, 0.0775*22.01g = 1.706moles then, 0.186g/1.705mol = 0.109g/mol then answer is 110g/mol where have i gone wrong?
thanks again DR BOB! this whole chemistry thing is a kick in the pants when you just cant get your head around it!
i need help. my assignmetn its due in less than 24 hrs. can anyone tell me where i went wrong?
just one thing on this dr bob, i thought that it was Ecell= E*cathode-E*anode. Why do you have a + sign between the 2. E1+E2? your way i get 0.35+(-0.13)=0.22, but my way i get 0.35-(-0.13)=0.48? which one?
thank you so much. I stuffed up at the start. i had 3 half-rxn. i didn't see that there was one for AgCl- it all makes thank. thankyou for your patience, It appriciated. I had to cram this subject in to get this assignment done. we are not supposed to
right then, numbers are- Br2 + 2e- = 2Br E=1.065V I2(s)+ 2e- = 2I- E=0.536V i have placed both these numbers into eq- Ecell= Ered(cathode)-Ered(anode) but for every combination, using the before mentioned eq, i cannot get any answers that they offer. If E
got my questions meixed up! I have tried this one by getting the 3 half-rxn and adding them up. then using E=E*-RT/nF InQ. i get close to an answer but not exact. i get 0.088V
Dr BOB, i just spoke to my lecturer and he says to use reduction potentials and half equations + Ecall=Ered(cathode)+Ered(anode). so i get half equ: 2Br->Br2+2e- E=-1.065V I2(s)+2e- -> 2I- E=0.536V from this i get Ecell=-1.601V but i don't know where to go
that is the full question. i cut and pasted it. i have emailed the lectures and have heard nothing...as usual. i have asked them if there should be more infor or a picture or something but nothing! how am i supposed to do it then?
thanks DR BOB, i did get that. they have given us an assignment for distant ed. students and we haven't even covered the topic yet. the assignment is due the day we start the electro chem topic! not good. thankyou
can someone pls help me with this as i am so confused and overwhelmed by this subject!
Dr BOB, can you explain, simply, how you do stage 3. or how you get the number of electrons? I just get myself so confused by it.
MnO4-?
