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  1. C

    Spectrum of Tandem MS

    Homework Statement There are four scan modes for tandem MS: Product ion, Precursor ion, Neutral loss scan mode and MRM. e.g. In MRM, the result of graph is Intensity versus time, but NOT versus m/z. What does the "time" in the graph refers to? Homework Equations The Attempt at a Solution...
  2. C

    TLC Rf order

    Homework Statement arrange the following eluents in an increasing order of Rf of aspirin ethyl acetate, n-hexane, n-butanol, methanol Homework Equations The Attempt at a Solution my order is n-hexane < n-butanol < ethyl acetate < methanol but the order is wrong. i am thinking: aspirin is...
  3. C

    Rank the acidity

    Homework Statement BCl3, BF3, B(CH3)3, B(CH3O)3 Rank the acidity of these compounds. Homework Equations The Attempt at a Solution I dont know how to determine the acidity of B(CH3O)3 and how the acidity of BF3 and BCl3 is higher than B(CH3)3 because of F and Cl high electronegativity. How...
  4. C

    Galvanic cell

    Homework Statement A is an aqueous solution of KCl(aq) with unknown concentration. The following experiment was carried out at 25°C to determine the concentration of Cl- (aq) in A, and the Ksp of AgCl(s) Step 1: A half-cell was made by dipping a silver strip into 100.0 cm3 of A. Step 2: A...
  5. C

    Acid dissociation constant

    Homework Statement when 10 cm3 of a monoprotic acid C3H6O3, with concentration of 7.2g/dm3, was titrated against against 0.05M NaCl, the equivalence point reached when 15.75cm3 (ph8) of NaOH was used. Calculate the acid dissociation constant Ka for C3H6O3. Homework Equations The Attempt at...
  6. C

    PH in buffer solution

    Ka values of the 1st and 2nd dissociation of phthalic acid (HO2C-C6H4-CO2H) are given below. Estimate the pH value for highest buffer capacity when a buffer is prepared from 1:1 mixture of phthalic acid and sodium hydrogen phthalate (HO2CC6H4- CO2Na) in water? HO2C-C6H4-CO2H <=> H+...