3. Chemical Reactions

Mass Percent

Multiple Choice
The following data were collected when analyzing a compound used in dentistry as a cement to repair teeth:

50.82% Zn;16.04% P;33.14% O

What is the empirical formula of the compound?
Multiple Choice
Based on the amounts of reactants used the calculated amount of product that can form for a given reaction was 20.76 g. When the reaction was carried out in a laboratory 17.34 g of product was recovered. What is the percent yield for this reaction?
Open Question
A compound whose empirical formula is XF₃ consists of 65% F by mass. What is the atomic mass of X?
Open Question
What is the mass % of carbon in dimethylsulfoxide (C₂H₆SO) rounded to three significant figures?
Open Question
Calculate the mass percent composition of lithium in Li₃PO₄.
Open Question
What is the percentage of nitrogen, by mass, in calcium nitrate?
Open Question
What is the percent composition for carbon and hydrogen in ethane C₂H₆?
Open Question
We dissolve 2.45 g of sugar in 200.0 g water. what is the mass percent of sugar in the solution?
Open Question
A 500 gram iron ore sample was determined to contain 242 grams of iron. What is the mass percent of iron in the ore?
Open Question
What mass of a 4.00% NaOH solution by mass contains 15.0 g of NaOH?
Open Question
A 69.5 g sample of the compound X₃O₄ contains 19.2 g of oxygen atoms. What is the molar mass of element X?
Open Question
Calculate the percent composition by mass of each element in Al(OH)₃. Use at least three significant figures.
Open Question
Aspirin is a compound with the molecular formula C₉H₈O₄. What is its percent composition?
Open Question
Calculate the mass percent composition of nitrogen in each of the following nitrogen compounds.
Open Question
Calculate the experimental mass % of c and h in the unknown liquid used in the experiment.