Question

Textrodotoxin is a toxic chemical found in fugu pufferish, a popular but rare delicacy in Japan. The compound has a LD50 (the amount of substance that is lethal to 50% of a population of iron (iii) hydroxide. Textrodotoxin is 41.38% carbon by mass, 13.16% nitrogen by mass, and 5.37% hydrogen by mass, with the remaining amount consisting of oxygen.

Answer 1

You didn't finish the question. I assume you want to know the empirical formula.
Take a 100 g sample,
That will give you
41.38 g carbon.
13.16 g nitrogen.
5.37 g hydrogen.
100-sum of above = g oxygen.

Convert each of the grams to moles, then find the ratio of them in small whole numbers. (Divide the smallest number by itself to make it 1.00, then divide all of the others by the same small number.) Round to whole numbers (but don't found anything between xx.25 and xx.75). I think you will come out with xx.67. The way to get rid of that is to multiply all of the numbers by 3 and you should get very close to whole numbers for all of them. This gives the reported empirical formula for the compound.

Answer 2

Thanks! That helps me a lot to answer the remaining parts of the question.