1. M

    Back Titration (or Indirect titration) to determine concentration of acetylsalicylic

    MW21 New Members 0 1 post Report post Posted 1 hour ago For school, we performed a back titration involving one brand of aspirin and were told to determine the quantity of acetylsalicylic acid in a single tablet. sodium hydroxide was added in excess then the solution was heated. the excess...
  2. R

    Determine Enthalpy Change

    Please help me answer and understand this: Chloroform, CHCl3, is formed by the following reaction: CH4(g) + 3 Cl2(g) → 3 HCl(g) + CHCl3 (g) Determine the enthalpy change for this reaction (ΔH°rxn), using the following: enthalpy of formation of CHCl3 (g), ΔH°f = – 103.1 kJ/mol...
  3. B

    Determine ΔE reaction for each of the following reactions?

    2NH3(g)+3O2(g)+2CH4(g)-->2HCN(g)+6H2O(g) 2Al(s)+3Cl2(g)-->2AlCl3(s) So i'm totally lost on how to go about this question. Help getting started would be greatly appreciated.
  4. T

    Determine Ti in Ilmenite sample using Inductively Coupled Plasma Mass Spectrometry

    How to determine Ti in Ilmenite sample using Inductively Coupled Plasma Mass Spectrometry?
  5. S

    How can you determine the mass, volume, or moles?

    I had a quiz today, and had no idea what the instructor expected us to do based off the information given. I'm trying to figure out how we were supposed to get the mass, volume, or moles to help solve the problems. I don't want any answers, just advice on how to use the information to get me to...
  6. J

    How would i determine the mass of the other Isotope PLEASE HELP

    Silver has two naturally occurring isotopes. The first, with a mass of 106.9 amu, has a natural abundance of 51.85%. Given its atomic weight of 107.9 amu, determine the mass of the other isotope. I know the answer is 109.0 amu. But how do you get it. Please Help...
  7. N

    Determine amount of base to use for titration?

    I am doing a lab in which I need to use a base with a known concentration (a standard solution that I have to dilute to make a secondary standard) to react with an acid with an unknown concentration. I then have to find the mass of the acid. I am wondering how I am supposed to find what...
  8. N

    HELP! Design an experiment using sequential qualitative analysis to determine whether

    I need help with the following chemistry question! Please help! Design an experiment using sequential qualitative analysis to determine whether a solution contains acetate or carbonate ions. For each stage of the test, write net ionic equations for the reaction that produces the precipitate.
  9. M

    determine small amount methanol in solutions

    i like homebrewing but i don't know how to realize my homemade alcohol is safe even existing small volume of methanol has high risk to make someone blind i have tested my alcohol with red litmus paper but methanol and ethanol bout of them make it blue so this not good method. i added dicromate...
  10. L

    How do I determine the molarity of an unknown from a redox titration?

    I titrated 10.00mL of 0.2 Molar (COOH)2 with 12.31mL of KMnO4. How would I determine the molarity of KMnO4? Balanced Net Ionic Equation (determined from half reactions) 2MnO4- + 6H+ + 5(COOH)2 ----> 10CO2 + 2Mn2+ + 8H2O Originally I tried doing it like this (below), but I don't feel too...
  11. S

    Determine the Percent Acetic Acid in Vinegar Sample

    :confused: Determine the percent acetic acid in the vinegar sample. (CH3COOH) -0.69 average molarity of vinegar solution -density of 0.2g/mL for the acid solution 10.0 M vinegar for titration 0.25 M NaOH solution Using a buret for titration: Volume of NaOH used : 14.6 NaOH(aq) + CH3COOH(aq)...
  12. Q

    How to determine Approx. Delta H using bond dissociation energies?

    Please explain the formula and values for the following reactions, as my book does not have a table to search for the bond dissociation values. Ethanol and Acetic Acid to form Ethyl Acetate Water and Propene to form Isopropyl Alcohol Thank you
  13. S

    Determine unknown conc from cruve!!

    Hello...ive been trying to determine for 3 days now a unknown. I have a calibration curve run on hplc with the following peak areas: Conc (mg/L) Peak Area 0 0 0.001 43162 0.01 1027039 0.05 4623058 0.1...