The percent composition by mass of an unknown chlorinated hydrocarbon was found to be 37.83%C, 6.35%H, and 55.83%Cl by mass. What is the empirical?

What mass of iron (III) oxide is produced when 3.88 X 1025 grams of oxygen reacts with excess iron?

In an experiment to determine the empirical formula of magnesium chloride, 0.50 g of magnesium ribbon was taken in a beaker and a few drops of HCl was added until all the Mg reacted with the acid liberating the hydrogen gas. The reaction completion was noted by observing that the bubbling stopped and no solid Mg was seen in the beaker. The beaker was heated to remove water and the dried magnesium chloride was weighed and found to be 1.99 g. What is the empirical formula for magnesium chloride based on this experiment?

0.333 g of a hydrocarbon (CxHy) was analyzed by combustion analysis and 1.009 g of CO2 (MM = 44.01 g/mol) and 0.516 g of H2O (MM = 18.02 g/mol).   How many moles of hydrogen were in the 0.333 g sample?  Enter your answer in standard notation to the proper number of significant figures.

An impure sample of table salt (NaCl) that was dissolved in water and treated with silver nitrate to form silver chloride. If the initial sample had a mass of 1.741 g and the final mass of the AgCl was found to be 4.084 g, what is the mass percent of NaCl in the impure sample?

8. An explosive has the following composition by mass: 15.87% Carbon, 2.22% Hydrogen, 18.5% Nitrogen and 63.41% Oxygen. What is the empirical formula of the explosive?

When copper is heated with an excess of sulfur, copper(I) sulfide is formed. In a given experiment, 1.50 g of copper was heated with excess sulfur to yield 1.64 g copper(I) sulfide. What is the percent yield?

When copper is heated with an excess of sulfur, copper(I) sulfide is formed. In a given experiment, 1.50 g of copper was heated with excess sulfur to yield 1.79 g copper(I) sulfide. What is the percent yield?

A compound contains arsenic (As) and oxygen as its only elements. A 1.626 gsample of the compound contains 1.060 g of arsenic.What is the empirical formula for the compound?If the molecular mass is 395.7 g/mol, what is the molecular formula for this compound?

A chemist goes into the lab and performs an experiment in which a mixture of 8.47 grams of Zn and 6.03 g of sulfur are reacted.  Before starting the experiment they perform the following calculations to predict the maximum (theoretical) yield of zinc sulfide that could be produced.   They obtain an actual yield of 8.25 grams of zinc sulfide.   Calculate their percent yield to one decimal place.