1. S

    Lattice energy problem; Where did I go wrong?

    I did 2(495) + 2(109) + 1/2(499) +(-603) +x = -416 x+854.5=-416 x= -1207.5 but this is wrong. Any tips/suggestions? Thanks!
  2. K

    What did i do wrong with this problem?

    Lithium nitride reacts with water to produce ammonia and lithium hydroxide according to the equation, Li3N(s)+3H2O(l) NH3(g)+3LiOH(aq) Heavy water is water with the isotope deuterium in place of ordinary hydrogen, and its formula is D2O. The above reaction can be used to produce heavy ammonia...
  3. W

    Please review my calculations for my titration lab and correct me where I'm wrong.

    DON'T BOTHER GUISE, I HAVE FOUND MY MISTAKES. HOW THE HECK DO I DELETE THIS ALTOGETHER? Aim: To determine the amount of Fe2+ in a dissolved wire solution. Method: 25cm^3 of a sol. Of iron wire in dilute sulphuric acid(some in the form of Fe3+ and some in the form of Fe2+) was pipetted and...
  4. C

    Correct if im wrong please

    Can you tell me if i am wrong or not im gearing up for a test. Write the net ionic equation LiOH(aq) + HClO2(aq) = LiClO2(s) + H20(aq) Li(aq) + ClO2(aq) = Li(ClO2)(s) NaOH(aq) + HBr(aq) = NaBr(s) + H20(aq) Na(aq) + Br(aq) = NaBr(s) 2K3PO4(aq) + 3NiCl2(aq) = 6KCl(aq) + Ni3(PO4)2(s)...
  5. G

    Wrong results in Vitamin C titration

    I have done a vitamin c back titration experiement with vitamin c fortified pineapple Juice to investigate the effects of temperature on vitamin c concentration. The samples were heated for 5 minutes at 20,40,60,80 and 100 degrees. My titre values were all concordant (within +/- 0.2ml) for each...
  6. L

    Please check the answers for my practice sheet. I need to know whats wrong ASAP.

    If there are any wrong answers, please let me know which ones they are and what needs to be done to fix them. 1. The graph shows the change in concentration of one of the species in the reaction AB A + B + heat. If the graph indicates the reaction rate, then the concentration of which species...