Problem 84
A sample of Freon was found to contain \(0.423 \mathrm{~g}\) of \(\mathrm{C}\), \(2.50 \mathrm{~g}\) of \(\mathrm{Cl}\), and \(1.34 \mathrm{~g}\) of \(\mathrm{F}\). What is the empirical formula of this compound?
Problem 85
Cinnamic acid, a compound related to the flavor component of cinnamon, is \(72.96 \%\) carbon, \(5.40 \%\) hydrogen, and the rest is oxygen. What is the empirical formula of this acid?
Problem 87
A dry-cleaning fluid composed of only carbon and chlorine was found to be composed of \(14.5 \% \mathrm{C}\) and \(85.5 \% \mathrm{Cl}\) (by mass). What is the empirical formula of this compound?
Problem 88
One compound of mercury with a molar mass of 519 contains \(77.26 \% \mathrm{Hg}, 9.25 \% \mathrm{C},\) and \(1.17 \% \mathrm{H}\) (with the balance being \(\mathrm{O}\) ). Calculate the empirical formula.
Problem 89
When \(0.684 \mathrm{~g}\) of an organic compound containing only carbon, hydrogen, and oxygen was burned in oxygen, \(1.312 \mathrm{~g}\) of \(\mathrm{CO}_{2}\) and \(0.805 \mathrm{~g}\) of \(\mathrm{H}_{2} \mathrm{O}\) were obtained. What is the empirical formula of the compound?
Problem 93
The following are empirical formulas and the masses per mole for three compounds. What are their molecular formulas? (a) \(\mathrm{NaS}_{2} \mathrm{O}_{3} ; 270.4 \mathrm{~g} / \mathrm{mol}\) (c) \(\mathrm{C}_{2} \mathrm{HCl} ; 181.4 \mathrm{~g} / \mathrm{mol}\) (b) \(\mathrm{C}_{3} \mathrm{H}_{2} \mathrm{Cl} ; 147.0 \mathrm{~g} / \mathrm{mol}\)
Problem 102
Balance the following equations. (a) \(\mathrm{CaO}+\mathrm{HNO}_{3} \longrightarrow \mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}+\mathrm{H}_{2} \mathrm{O}\) (b) \(\mathrm{Na}_{2} \mathrm{CO}_{3}+\mathrm{Mg}\left(\mathrm{NO}_{3}\right)_{2} \longrightarrow \mathrm{MgCO}_{3}+\mathrm{NaNO}_{3}\) (c) \(\left(\mathrm{NH}_{4}\right)_{3} \mathrm{PO}_{4}+\mathrm{NaOH} \longrightarrow\) \(\mathrm{Na}_{3} \mathrm{PO}_{4}+\mathrm{NH}_{3}+\mathrm{H}_{2} \mathrm{O}\) (d) \(\mathrm{LiHCO}_{3}+\mathrm{H}_{2} \mathrm{SO}_{4} \longrightarrow \mathrm{Li}_{2} \mathrm{SO}_{4}+\mathrm{H}_{2} \mathrm{O}+\mathrm{CO}_{2}\) (e) \(\mathrm{C}_{4} \mathrm{H}_{10} \mathrm{O}+\mathrm{O}_{2} \longrightarrow \mathrm{CO}_{2}+\mathrm{H}_{2} \mathrm{O}\)
Problem 109
Write the equation that expresses in acceptable chemical shorthand the following statement: "Iron can be made to react with molecular oxygen to give iron(III) oxide."
Problem 110
The conversion of one air pollutant, nitrogen monoxide, produced in vehicle engines, into another pollutant, nitrogen dioxide, occurs when nitrogen monoxide reacts with molecular oxygen in the air. Write the balanced equation for this reaction.
Problem 111
A balanced chemical equation contains the term \(“ 2 \mathrm{Ba}(\mathrm{OH})_{2} \cdot 8 \mathrm{H}_{2} \mathrm{O} .\) " How many atoms of each element does this represent in the molecular view? How many moles of each element does this represent on the laboratory scale?
