Sergey Bylikin, Gary Horner and, Brian Murphy Solutions for Chapter: Stoichiometric Relationships, Exercise 15: Questions

Assuming complete reaction, what volume of $0.200 \mathrm{mol} {\mathrm{dm}}^{-3}$ potassium hydroxide solution, $\mathrm{KOH}$, is required to neutralise $25.0 {\mathrm{cm}}^3$ of $0.200 \mathrm{mol} {\mathrm{dm}}^{-3}$ aqueous sulphuric acid, ${\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)$? 

Copper metal may be produced by the reaction of copper($\mathrm{I}$) oxide and copper($\mathrm{I}$) sulphide according to the equation $2{\mathrm{Cu}}_2\mathrm{O}+{\mathrm{Cu}}_2\mathrm{S}\stackrel{ }{\to }6\mathrm{Cu}+{\mathrm{SO}}_2$. A mixture of $10.0 \mathrm{kg}$ of copper($\mathrm{I}$) oxide and $5.00 \mathrm{kg}$ of copper($\mathrm{I}$) sulphide was heated until no further reaction occurred. Determine the limiting reagent, in this reaction, showing your working.

Copper metal may be produced by the reaction of copper($\mathrm{I}$) oxide and copper($\mathrm{I}$) sulphide according to the equation $2{\mathrm{Cu}}_2\mathrm{O}+{\mathrm{Cu}}_2\mathrm{S}\stackrel{ }{\to }6\mathrm{Cu}+{\mathrm{SO}}_2$. A mixture of $10.0 \mathrm{kg}$ of copper($\mathrm{I}$) oxide and $5.00 \mathrm{kg}$ of copper($\mathrm{I}$) sulphide was heated until no further reaction occurred. Calculate the maximum mass of copper that could be obtained from these masses of reactants.

A toxic gas, $\mathrm{A}$ consists of  $53.8\%$ nitrogen and $46.2\%$ carbon by mass. At $273 \mathrm{K}$ and $1.01\times {10}^5 \mathrm{Pa}$, $1.048 \mathrm{g}$ of $\mathrm{A}$ occupies $462 {\mathrm{cm}}^3$. Determine the empirical formula of $\mathrm{A}$. Calculate the molar mass of the compound and determine its molecular structure. 

An oxide of copper was reduced in a stream of hydrogen. After heating, the stream of hydrogen gas was maintained until the apparatus had cooled. The following results were obtained.

Mass of empty dish$=13.80 \mathrm{g}$, mass of dish and contents before heating$=21 75 \mathrm{g}$ and  mass of dish and contents after heating and leaving to cool$=20.15 \mathrm{g}$.

Explain why the stream of hydrogen gas was maintained until the apparatus cooled.

An oxide of copper was reduced in a stream of hydrogen. After heating, the stream of hydrogen gas was maintained until the apparatus had cooled. The following results were obtained.

Mass of empty dish$=13.80 \mathrm{g}$, mass of dish and contents before heating$=21.75 \mathrm{g}$ and the mass of dish and contents after heating and leaving to cool$=20.15 \mathrm{g}$.

Calculate the empirical formula of the oxide of copper using the data above, assuming complete reduction of the oxide.

An oxide of copper was reduced in a stream of hydrogen. After heating, the stream of hydrogen gas was maintained until the apparatus had cooled. The following results were obtained.

Mass of empty dish$=13.80 \mathrm{g}$, mass of dish and contents before heating$=21 75 \mathrm{g}$ and  mass of dish and contents after heating and leaving to cool$=20.15 \mathrm{g}$.

Write an equation for the reaction that occurred.

An oxide of copper was reduced in a stream of hydrogen. After heating, the stream of hydrogen gas was maintained until the apparatus had cooled. The following results were obtained.

Mass of empty dish$=13.80 \mathrm{g}$, mass of dish and contents before heating$=21 75 \mathrm{g}$ and  mass of dish and contents after heating and leaving to cool$=20.15 \mathrm{g}$.

State two changes that would be observed inside the tube as it was heated.