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A compound has been analyzed and has been found to have the following composition: copper, \(66.75 \%\); phosphorus, \(10.84 \%\); oxygen, \(22.41 \%\). Determine the empirical formula of the compound.

Tetraphenylporphyrin is a synthetic compound that resembles naturally occurring porphyrins. Porphyrins are found in hemoglobin and cytochromes, which are important to biological functions in humans. Tetraphenylporphyrin is composed of only \(\mathrm{C}, \mathrm{H},\) and \(\mathrm{N}\) atoms. Experiments show that tetraphenylporphyrin is \(85.96 \% \mathrm{C}\) and \(4.92 \% \mathrm{H}\) by mass. What is the empirical formula of tetraphenylporphyrin?

When \(1.00 \mathrm{mg}\) of lithium metal is reacted with fluorine gas \(\left(\mathrm{F}_{2}\right),\) the resulting fluoride salt has a mass of \(3.73 \mathrm{mg}\). Calculate the empirical formula of lithium fluoride.

Phosphorus and chlorine form two binary compounds, in which the percentages of phosphorus are \(22.55 \%\) and \(14.87 \%\), respectively. Calculate the empirical formulas of the two binary phosphorus-chlorine compounds.

How does the molecular formula of a compound differ from the empirical formula? Can a compound's empirical and molecular formulas be the same? Explain.

A binary compound of boron and hydrogen has the following percentage composition: \(78.14 \%\) boron, \(21.86 \%\) hydrogen. If the molar mass of the compound is determined by experiment to be between 27 and \(28 \mathrm{~g},\) what are the empirical and molecular formulas of the compound?

A compound with empirical formula CH was found by experiment to have a molar mass of approximately 78 g. What is the molecular formula of the compound?

A compound with the empirical formula \(\mathrm{CH}_{2}\) was found to have a molar mass of approximately \(84 \mathrm{~g}\). What is the molecular formula of the compound?

A compound with empirical formula \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{O}\) was found in a separate experiment to have a molar mass of approximately \(90 \mathrm{~g}\). What is the molecular formula of the compound?

A compound having an approximate molar mass of \(165-170 \mathrm{~g}\) has the following percentage composition by mass: carbon, \(42.87 \%\); hydrogen, \(3.598 \%\); oxygen, \(28.55 \%\); nitrogen, \(25.00 \%\). Determine the empirical and molecular formulas of the compound.