Oxalic acid, an organic compound found in plants and vegetables such as rhubarb, has a mas...

Oxalic acid, an organic compound found in plants and vegetables such as rhubarb, has a mass percent composition of 26.7% C, 2.24% H, and 71.1% O. Oxalic acid can interfere with respiration and cause kidney or bladder stones. If a large quantity of rhubarb leaves is ingested, the oxalic acid can be toxic. The lethal dose (LD50) in rats for oxalic acid is 375 mg/kg. Rhubarb leaves contain about 0.5% by mass of oxalic acid.

a. What is the empirical formula of oxalic acid?

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b. If oxalic acid has an experimental molar mass of 90. g, what is its molecular formula?

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c. Using the LD50, how many grams of oxalic acid would be toxic for a 160-lb person?

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d. How many kilograms of rhubarb leaves would the person in part c need to eat to reach the toxic level of oxalic acid?