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Homework Help: Need help on two questions (electron configuration and stoichiometry

  1. Jan 14, 2010 #1
    A compound is analyzed and it contains H,N,O and C. The original sample is 1.3957 grams. The sample is burned in excess oxygen to form 2.24 grams of CO2. 0.04 grams H is evaluated in the original sample.

    a. What are the grams of oxygen in the original sample?
    b. The original compound contains 28.84% N, how many grams of N are there?
    c. How many grams of C are in the original compound?
    d. What is the empirical formula for this compound?

    How would you do this step by step and what are the solutions?

    I was only able to get part B which was .0403 grams i believe?

    I have a midterm tomorrow and need urgent help.

    Thank you
    Last edited: Jan 14, 2010
  2. jcsd
  3. Jan 15, 2010 #2
    b- correct
    c- how many moles of C are in 2.24 grams of CO2? What is that in grams?
    a- Subtract b, c, and 0.04 grams H from the original sample weight. That gives you the amount of oxygen in the original compound.
    d-after you find everything in grams you can covert it to moles. Find the ratios between each government.
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