Help me please!!! Chemistry students only...?
399443
starting HCl moles = .05mol\n\n\nexcess HCl moles in 250cm^3 = .02105mol\n\nHCl moles reacted with 1.5 g of CaCO3 sample,\n\n\n(starting HCl moles )minus (excess HCl moles )=.05mol - .02105mol = .02895 mol\n\n\n\nequation:\n\n\nCaCO3(s) + 2HCl(aq) -->  CaCl2(aq) + H2O(l) + CO2(g)\n\n\nmole ratio =  HCl 2:1 CaCO3\n\n\ndivide by 2 ,( .02895mol / 2  = .014475mol of HCl)\n\n\n\ngrams of CaCO3 =  .014475 * 100g = 1.14475g of CaCO3\n\n\nCaCO3 % = (1.14475g / 1.5g )*100 =  96.5 %
58627
OK. You've posted this (and several other) questions(with exactly the same words and numbers) for the fourth day in a row, and everytime you've asked, one person has responded and we've all got different answers. \n\nI can't tell if you're a student that's gonna keep posting until several people give you the same answer, of if you're just someone that likes making the nerdy people solve chem problems. If you're the latter, you should really find a better use for your time. \n\nIf you're the former, try working the problem yourself and then compare your answers to ours, or compare our approaches, your notes, and textbook and see where they differ. Our different answers can probably be attributed to some math or conversion error. \n\nRemember, when all else fails follow the units and you'll be right more times than not.
66304
Send me an IM at jammin246 on yahoo I'll walk you through any chemistry problems you might be facing.
383259
go to\nwww.chemistry.com
892172
44 A) 2AgO --> 4Ag + O2\n     B)NiCO3 --> NiO + CO2\n     C)NH4NO3 --> N2O + 2H2O\n48)A)2HCl + Ca(OH)2 --> CaCl2 + 2H2O\n     B)3Ag2SO4 + 2AlCl3--> 6AgCl + Al2(SO4)3\n     C)&D) I've no idea, sry\n50)A)C4H8 + 6O2 --> 4CO2 + 4H2O\n     B)2C8H18 + 25O2 --> 16CO2 + 18H2O\n     C)2C3H8O3 + 7O2 --> 6CO2 + 8H2O\n     D)2C3H6O + 5O2 --> 6CO2 + 6H2O\n52)A)2Al + 3H2SO4 --> Al2(SO4)3 + 3H2\n     B)2HCl + Ba(OH)2--> BaCl2 + 2H2O\n     C)Au + HCl--> No Reaction(gold is below hydrogen in the metal reactivity series)\n54)A)2Cl2 + 2NaI --> 2NaCl2 + I2\n     B)2NH3--> N2 + 3H2\n     C)4Na + O2--> 2Na2O\n     D)Mg + H2SO4--> MgSO4 + H2\n     E)MgCl2 + Ca(OH)2--> Mg(OH)2 + CaCl2\n     F)H2 + Cl2--> 2HCl
791178
I HAVE A CHEMISTRY EXAM tomorrow. Actually a small test.lol\nwant answers go to the site below!
359558
i learned about this in chem.  it's hard to explain...but if you put a cd in your microwave(if your parents allow u 2) then you can see it.  if u need help, you could e-mail my teacher by getting his e-mail address from his website below.  hope that helps!
72603
Wow, I hope these are right.  I wish i had a solubility chart or something (Which you probably have)  \n\nCuSO4(aq) + Na2S(aq) ---> CuS (s) + NaSO4 (aq)\nNet ionic - Cu2+ (aq) + S2- (aq)  ---> CuS (s)\n\nNiCl2 + 2KNO3 --> Ni(NO3)2 (aq) + 2KCl (aq)\nnet ionic - none (if NiCl2 isn't aq, then this is wrong)\n\nCa(OH)2 + 2HC2H3O2 ---> Ca(C2H3O2)2 (aq) + 2H2O (l) \nnet ionic - H+ (aq) + OH-(aq) ---> H2O (l)\nactually, since the acetic acid is a weak acid, this might be a little different.  If you learned it this way, then your net ionic is:\nHC2H3O2 (aq) + OH- (aq) ---> H2O (l) + C2H3O2- (aq)\n\nHope this helped
310484
http://chemistry.about.com/library/weekly/blsapon.htm\n\n\n\nSimple web search
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Hey, Blond fuss?  Good luck if U can't find help @ this late hour. Keep working on it.  Something from what U learned so far must b in your head - find it. No one else working on this problem awake?\n  I'm tired (12:35 a.m. here @ UMAss Amherst).  Had 1st-yr Chem 100 in 1978, not Chem 1111 !! Barely remember orbitals.  U do have books there, don't U?   Library maybe not open now as ours is.    \n Aces 2 computer. So U have awhile 2 figure it out.  Good luck.
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http://www.sbuniv.edu/~ggray/CHE3345/chp14.html\nhttp://web.odu.edu/sci/tisenhou/chem321/chap12/index.htm\n\nbest luck
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http://www.chem.uni-potsdam.de/~thomas/1hbuch/english/index.html\n\nhere is a website that seems short and simple\ngood luck
574078
This might help :)\nhttp://www.chemicalforums.com/index.php?board=8;action=display;threadid=3263
1049588
I think that you are trying to find the net ionic equation. \nWhich in this case would be \nAg+ (aq) + Br- arrow AgBr (solid)\nif you are trying to find a single replacement reaction?\nthen you need to put Br- instead of NO3- and cancel out the NO3 - on the product side? \nTried my Best.
660043
1.) do your own homework\n2.) this is the computer forum, not high-school chemistry.  Next time post to the right furom.
683249
Oh, come on, it doesn't get any easier than this!\n\nSnO2 + 2H2 --> Sn + 2H2O\n\nAbove is balanced. 1 Sn on both sides, 2 O on both sides and 4 H on both sides.\nYou need to work a little harder on these yourself.
740485
Look up in Hand book of chemistry and mathematics, you school library will have it. Your professor should also have it.