General Chemistry 1: Chemical Formulas

Given a molar mass of 116.24 g/mol and an empirical formula of C$_3$H$_8$N, find the molecular formula for this compound.

Calculate the mass percentages of the elements in CO$_2$

Stupidium is a fictional element with 2 isotopes, $^35$St with a mass of 34.9567 g/mol, and $^39$St with a mass of 39.0095 g/mol. The molar mass of St is 35.9826 g/mol. What are the percent abundances of the isotopes?

Naturally occurring boron is composed of 19.8% of $^{10}$B and 80.2% of $^{11}$B. Atoms of $^{10}$B have a mass of of 10.0129 u and those of $^{11}$B have a mass of 11.0093 u. Calculate the average atomic mass of boron.