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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? Assume a density of 1.01g/mL.

15 years ago

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 e-® Co E°cell = -0.28 V Cr+3 + 3 e-® Cr E°cell = -0.74 V The strongest oxidizing agent listed above is: Cr3+. Cr. Mn2+. Co2+. Mn...

15 years ago

Given a cell based on the spontaneous reaction 2AgCl(s) + Zn(s) ® 2Ag(s) + 2Cl– + Zn2+ If the zinc ion concentration is kept constant at 1 M, and the chlorine ion concentration is decreased from 1 M to 0.001 M, the cell voltage should increase by 0.06 V i...

15 years ago

Complete and balance the following equations using the method of half-reaction. both reactions happen in acidic solutions: a. Cu(s) + NO3-(aq)--> Cu2+(aq) + NO2(aq) b. Mn2+(aQ) + NaBiO3(s)--> Bi3+(aq) + MnO4-(aq) I'm having trouble getting the half-rxn eq...

15 years ago

A cell can be prepared from copper and tin. What is the E° cellfor the cell that forms from the following half reactions? Cu2+(aq) + 2e-Cu(s) E° = 0.35 V Sn4+(aq) + 2e- Sn2+(aq) E° = 0.13 V a. 0.48 V b. 0.22 V c. -0.48 V d. -0.22 V

15 years ago

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 question- as writen, no values, nothing. any help

15 years ago

Complete and balance the following redox equation. The sum of the coefficients when they are all whole numbers is MnO4- + H+ + Br-® Mn2+ + Br2 + H2O (acidic solution) 6 17 21 29 43

15 years ago

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 get the wrong answer. i have the half-rxn and fugured out E=0.536. then used eq dG=-nFE, followed by dG=-RTInK. PLS HELP

15 years ago

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 trouble with the order of reactions. I don't understand this question. this is an assignment question but i have no idea how to...

15 years ago

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 = 3.5 x 104 s-1 at 25° C, what is the activation energy for the decomposition? 0.73 kJ/mol 58 kJ/mol 140 kJ/mol 580 kJ/mol I am...

15 years ago

this is a text book question that i cannot figure out. the decomposition of dimethyl ether at 510 degrees is a first-order process with a rate constant of 6.8*10^-4. (CH3)2O(g)--> CH4(g) + H2(g) + CO(g) if the partial pressure of (CH3)20 is 18kPa, what is...

15 years ago

the vapour pressure of pure water at 110 degrees is 142.7kpa. a solution of ethylene glycol and water has a vapour pressure of 101.3kpa at 110 degrees. assuming that raoults law is obeyed, what is the mole fraction of ethylene glycol in the solution? I ge...

15 years ago

camphor melts at 179.8 degrees, and it has a particularly high freezing point depression constant.(kf=40 degrees/m). when 0.186g of an organic substance of an unknown molar mass is dissolved in 22.01g of liquid camphor, the freezing point of the mixture i...

15 years ago

MnO4-?

15 years ago

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.

15 years ago

can someone pls help me with this as i am so confused and overwhelmed by this subject!

15 years ago

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

15 years ago

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?

15 years ago

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 g...

15 years ago

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

15 years ago

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...

15 years ago

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 sta...

15 years ago

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?

15 years ago

i need help. my assignmetn its due in less than 24 hrs. can anyone tell me where i went wrong?

15 years ago

thanks again DR BOB! this whole chemistry thing is a kick in the pants when you just cant get your head around it!

15 years ago

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?

15 years ago

so doing it your way you then habe to times it by 1000 to get it back to g/mol.

15 years ago