1. P

    I've been trying to get the right answer but it doesn't work!

    This problem is from Chemistry and Chemical Reactivity, 8th Edition. A spool of copper wire has a mass of 4.26 kg. How long is the wire in the spool if the wire has a diameter of 2.2 mm? (The density of copper is 8.96 g/cm^3. The answer is 130 m, but I keep getting 1.2*10^2 m. Am I doing...
  2. C

    Chemistry Homework Answer

    Hi, help me please to solve this. If 200.0 g of copper(ll) sulfate react with an excess of zinc metal, what is the theoretical yield of copper? I am desperate, I am looking for help here and at but I still need an answer.
  3. M

    double check a chemistry answer

    I found this question online, I am being asked the exact question for an assignment however I don't know if it is right. The reason for this, is that when I try to calculate the percentage error it gives me an unrealistic percentage. Any help will be greatly appreciated! Hi, I was hoping...
  4. L

    I'm not sure which formula to use here and what is the right answer.

    The problem states, "How many milliliters of 0.750 M H3PO4 are required to react with 250. mL of 0.150 M Ba(OH)2 if the products are barium phosphate and water?" I saw two different ways to do this: with (M)(V)=(M)(V) or with M= moles of soulute/L solution. I worked it both ways and got 50.0mL...
  5. W

    Chemistry Molarity question, can you answer this??

    Equal Volumes of 0.5M H2S04 and 0.4M KOH are mixed. Calculate the molarity of each ion present in the final solution. since the volumes are equal, we can assume that its 1000ml (1L) so the mass of H2SO4 becomes 49g and KOH becomes 28.5g since number of moles equals given mass/molar mass. Now...
  6. V

    plz answer dis ques

    how does picolinic acid reacts with trichloroacetic acid. wanna to grow single crystal by mixing these two chemicals. so please do xpln me the basic chemistry behind these chem rxn
  7. L

    Incorrect answer

    For a solution containing 122mg/dL of Fe, how many grams are dissolved per liter of solution? I got one answer. The book gave a different answer and in the wrong units and my professor says the answer is right but the units are wrong. Here is what I'm doing: 122mg/dL x 1g/1000mg x...
  8. S

    Need help, got answer but it's incorrect.

    Suppose that the KMnO4 (aq) were standardized by reaction with As2O3. As2O3 + MnO4^- + H+ + H2O ---> H3AsO4 + Mn2+ (not balanced) If a 0.1342g sample that is 97.8% As2O3 by mass had been used in the titration, how many milliliters of the 0.0214 M KMnO4 (aq) would have been required? I got...
  9. M

    cant find the answer to this anywhere in the book

    In the reaction 2 MnO4 -(aq) + 10 Br-(aq) + 16 H+(aq) → 2 Mn2+ (aq) +5 Br2(aq) + 8 H2O(aq) the reducing agent is ________. Express your answer as a chemical formula.
  10. P

    Answer Verification

    Here's the problem: Bryan Allen made aviation history by pedaling the Gossamer Albatross from near Folkestone, England to Cap Gris Nez, France, from 4:51 AM to 7:40 AM on June 12, 1979. During this flight, he continually produced about a third of a horsepower (1hp=0.7451997 KJ/s). Consider that...
  11. A

    why not answer?

    why is it they don't answer question anymore.just a hint!:eek: