A sample of an iron oxide weighing 0.982 g is found to contain 0.763 g of iron. The rest of the mass is oxygen. Determine the empirical formula of the compound.

If 34.2 grams of lithium react with excess water, how many liters of hydrogen gas can be produced at 299 kelvin and 1.21 atmospheres? 2 li (s) + 2 h2o (l) yields 2 lioh (aq) + h2 (g)

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?

What kind of intermolecular forces act between a hydrogen fluoride molecule and a hydrogen peroxide molecule? note: if there is more than one type of intermolecular force that acts, be sure to list them all, with a comma between the name of each force.