How many atoms of aluminum are present in a sample that has a mass of 155.30 g?

Answer: 3.47 x 10^24

What is the percent composition of sodium hydrogen carbonate (NaHCO3)?

Answer: Na = 27.36%, H = 1.20%, C = 14.30%, O = 57.14%

If a compound has a molar mass of 180 g/mol and its empirical formula is CH2O, what is its molecular formula?

Answer: C6H12O6

What is the percent by mass of magnesium sulfate in MgSO4 · 7H2O?

Answer: 48.83%

What is the percent by mass of carbon in C10 H14 N2?

Answer: 74.02%

A sample of a compound contains 32.0 g C and 8.0 g H. Its molar mass is 30.0 g/mol. What is the compound's molecular formula?

Answer: C2H6