🤓 Based on our data, we think this question is relevant for Professor Rubin's class at UCSC.
Since the given percentages are % by mass, let’s assume a 100 g of sample of E3H8.
Assume Mass of each component (% to g):
A binary compound between an unknown element E and hydrogen contains 91.27% E and 8.73% H by mass. If the formula of the compound is E3H8. Calculate the atomic mass of E.