Answer:
To determine the molecular formula of a compound, you need to know its empirical formula and its molecular mass. The empirical formula is the simplest whole-number ratio of the atoms in a compound, and the molecular mass is the mass of a molecule of the compound, expressed in atomic mass units (amu).
In this case, the compound has an empirical formula of CH3, which means it is made up of one carbon atom and three hydrogen atoms. The molar mass of the compound is 41.98 g/mol, which means that one mole of the compound has a mass of 41.98 grams.
To find the molecular formula, you need to determine the number of atoms of each element in one mole of the compound. You can do this by dividing the molar mass of the compound by the atomic mass of each element. For example:
Number of carbon atoms = 41.98 g/mol / 12.01 amu/atom = 3.5 atoms
Number of hydrogen atoms = 41.98 g/mol / 1.01 amu/atom = 41.5 atoms
Since you can't have a fraction of an atom, you need to round these values to the nearest whole number. In this case, you would round up to get 4 carbon atoms and 42 hydrogen atoms. The molecular formula of the compound is therefore C4H42.
So, the correct answer is C. C5SH10.
I hope this helps! Let me know if you have any other questions.