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A compound has general formula C_aH_bO_cN_d and molecular weight 187. A 935 mg/L solution of the compound is prepared in distilled deionized water. The Total Organic Carbon (TOC) is measured as 360 mg/L (as C). The Chemical Oxygen Demand (COD) and the Total Kjeldahl Nitrogen (TKN) are determined as 800 mg/L (as O2) and 140 mg/L (as N), respectively (as per the chemical equation given below). Which of the following options is/are CORRECT? C_aH_bO_cN_d + ((4a+b-2c-3d)/4) O2 -> aCO2 + ((b-3d)/2) H2O + dNH3 Atomic weight: C(12), H(1), O(16), N(14)

1. a = 6
2. b = 7
3. c = 5
4. d = 3

Correct answer: a = 6

Solution

The correct option a = 6 is right because it satisfies the molecular weight of the compound when calculated using the general formula and the provided atomic weights. Substituting a = 6 into the equation allows for the correct balancing of carbon, hydrogen, oxygen, and nitrogen, aligning with the total molecular weight of 187.

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