MCAT Question of the Day
    •

    Q:

    		 The molecular mass of KOH is 56. In a reaction with another compound X, 1 mol of KOH is added to 1 mol of compound X. Compound X has a molecular mass of 200. The matrix of the reaction is only water, and upon rotary evaporation, 238 grams of product are recovered. Assuming 100% recovery of the product and a 100% completed reaction, what is the most likely explanation for the mass discrepancy?
    		 

    A

    		 The caustic solution reacted with compound X in such a way that volatile compounds were liberated and later evaporated

    B

    		 The K+ replaced the H on -OH, allowing the H to react with OH- to form water which was evaporated

    C

    		 Two OH- for each KOH reacted with compound X to give a mass of 238 grams

    D

    		 There is no mass discrepancy; 238 is the maximum amount of product that can be recovered from the reaction



    Stoichiometry | Quantitative Skills |
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