Problem 97
Ethylene \(\left(\mathrm{C}_{2} \mathrm{H}_{4}\right)\), an important industrial organic chemical, can be prepared by heating hexane \(\left(\mathrm{C}_{6} \mathrm{H}_{14}\right)\) at \(800^{\circ} \mathrm{C}\) : $$ \mathrm{C}_{6} \mathrm{H}_{14} \stackrel{\Delta}{\longrightarrow} \mathrm{C}_{2} \mathrm{H}_{4}+\text { other products } $$ If the yield of ethylene production is 42.5 percent, what mass of hexane must be used to produce \(481 \mathrm{~g}\) of ethylene?
Problem 98
When heated, lithium reacts with nitrogen to form lithium nitride: $$ 6 \mathrm{Li}(s)+\mathrm{N}_{2}(g) \stackrel{\Delta}{\longrightarrow} 2 \mathrm{Li}_{3} \mathrm{~N}(s) $$ What is the theoretical yield of \(\mathrm{Li}_{3} \mathrm{~N}\) in grams when \(12.3 \mathrm{~g}\) of \(\mathrm{Li}\) is heated with \(33.6 \mathrm{~g}\) of \(\mathrm{N}_{2}\) ? If the actual yield of \(\mathrm{Li}_{2} \mathrm{~N}\) is \(5.89 \mathrm{~g}\), what is the percent vield of the reaction?
Problem 99
Disulfide dichloride \(\left(\mathrm{S}_{2} \mathrm{Cl}_{2}\right)\) is used in the vulcanization of rubber, a process that prevents the slippage of rubber molecules past one another when stretched. It is prepared by heating sulfur in an atmosphere of chlorine: $$ \mathrm{S}_{8}(l)+4 \mathrm{Cl}_{2}(g) \stackrel{\Delta}{\longrightarrow} 4 \mathrm{~S}_{2} \mathrm{Cl}_{2}(l) $$ What is the theoretical yield of \(\mathrm{S}_{2} \mathrm{Cl}_{2}\) in grams when \(4.06 \mathrm{~g}\) of \(\mathrm{S}_{8}\) is heated with \(6.24 \mathrm{~g}\) of \(\mathrm{Cl}_{2}\) ? If the actual yield of \(\mathrm{S}_{2} \mathrm{Cl}_{2}\) is \(6.55 \mathrm{~g},\) what is the percent yield?
Problem 104
Determine whether each of the following equations represents a combination reaction, a decomposition reaction, or a combustion reaction: (a) \(2 \mathrm{NaHCO}_{3} \longrightarrow\) \(\mathrm{Na}_{2} \mathrm{CO}_{3}+\mathrm{CO}_{2}+\mathrm{H}_{2} \mathrm{O},(\mathrm{b}) \mathrm{NH}_{3}+\mathrm{HCl} \longrightarrow \mathrm{NH}_{4} \mathrm{Cl}\) (c) \(2 \mathrm{CH}_{3} \mathrm{OH}+3 \mathrm{O}_{2} \longrightarrow 2 \mathrm{CO}_{2}+4 \mathrm{H}_{2} \mathrm{O}\)
Problem 105
Determine whether each of the following equations represents a combination reaction, a decomposition reaction, or a combustion reaction: (a) \(\mathrm{C}_{3} \mathrm{H}_{8}+\) \(5 \mathrm{O}_{2} \longrightarrow 3 \mathrm{CO}_{2}+4 \mathrm{H}_{2} \mathrm{O},(\mathrm{b}) 2 \mathrm{NF}_{2} \longrightarrow \mathrm{N}_{2} \mathrm{~F}_{4}\) (c) \(\mathrm{CuSO}_{4} \cdot 5 \mathrm{H}_{2} \mathrm{O} \longrightarrow \mathrm{CuSO}_{4}+5 \mathrm{H}_{2} \mathrm{O} .\)
Problem 108
The atomic mass of element \(\mathrm{X}\) is 33.42 amu. A \(27.22-\mathrm{g}\) sample of \(\mathrm{X}\) combines with \(84.10 \mathrm{~g}\) of another element \(\mathrm{Y}\) to form a compound XY. Calculate the atomic mass of Y.
Problem 109
How many moles of \(\mathrm{O}\) are needed to combine with \(0.212 \mathrm{~mol}\) of \(\mathrm{C}\) to form (a) \(\mathrm{CO}\) and \((\mathrm{b}) \mathrm{CO}_{2} ?\)
Problem 110
The aluminum sulfate hydrate \(\left[\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3} \cdot x \mathrm{H}_{2} \mathrm{O}\right]\) contains 8\. 10 percent \(\mathrm{Al}\) by mass. Calculate \(x\), that is, the number of water molecules associated with each \(\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}\) unit.
Problem 111
A sample of a compound of \(\mathrm{Cl}\) and \(\mathrm{O}\) reacts with an excess of \(\mathrm{H}_{2}\) to give \(0.233 \mathrm{~g}\) of \(\mathrm{HCl}\) and \(0.403 \mathrm{~g}\) of \(\mathrm{H}_{2} \mathrm{O}\) Determine the empirical formula of the compound.
Problem 112
The carat is the unit of mass used by jewelers. One carat is exactly \(200 \mathrm{mg}\). How many carbon atoms are present in a 2 -carat diamond?
