Chapter Questions
Explain why living organisms maintain a relatively constant level of ${ }^{14} \mathrm{C}$.
The major industrial use of carbon is as a reducing agent. Write equations for three important processes that employ carbon as a reducing agent.
Write balanced equations to show the difference between methanides and acetylides in their reaction with water.
Show clearly why it is the carbon end of the $\mathrm{CO}$ molecule that binds to metals when carbon monoxide complexes are formed.
Consider a -1 ion that contains one atom each of $\mathrm{C}, \mathrm{S}$, and $\mathrm{P}$. Draw the correct structure, and explain why any other arrangements of atoms are unlikely.
Draw the molecular orbital energy level diagram for the $\mathrm{C}_2{ }^{2-}$ ion. Identify three species that are isoelectronic with $\mathrm{C}_2{ }^{2-}$.
Describe the process of casehardening of steel.
Using equations for the reactions, show how lime functions in mortar.
Predict some of the chemical characteristics of $\mathrm{CSe}_2$.
Write complete, balanced equations to show the following processes.(a) The reaction of $\mathrm{Ca}\left(\mathrm{HCO}_3\right)_2$ with aqueous $\mathrm{NaOH}$(b) The preparation of calcium cyanamide(c) The oxidation of potassium cyanide with $\mathrm{H}_2 \mathrm{O}_2$(d) The reaction of methane with sulfur vapor(e) The reaction of acetylene with sodium hydroxide
Draw the structure for the $\mathrm{C}_3 \mathrm{O}_2$ molecule. Identify all the symmetry elements it possesses, and assign the point group (symmetry type).
Explain why $\mathrm{Co}(\mathrm{CO})_4$ is not a stable molecule but solids containing the $\mathrm{Co}(\mathrm{CO})_4{ }^{-}$ion are known.
Explain why the stable carbonyl of vanadium is not $\mathrm{V}(\mathrm{CO})_6$ but is rather $\left[\mathrm{V}(\mathrm{CO})_6\right]_2$.
Would a solution of $\mathrm{NH}_4 \mathrm{CN}$ be acidic, basic, or neutral? For $\mathrm{NH}_3, K_{\mathrm{b}}=1.8 \times 10^{-5}$ and for $\mathrm{HCN}, K_{\mathrm{a}}=7.2 \times 10^{-10}$. Write equations to help you arrive at your answer.
What would be the products of heating solid $\mathrm{BaCS}_3$ ?
Draw resonance structures for the molecule containing one atom each of $\mathrm{C}$, $\mathrm{S}$, and $\mathrm{Se}$. Estimate the contribution of each structure. What experimental techniques could you use to determine if the contributions you assign are reasonable?
The formation of $\beta$-graphite from $\alpha$-graphite is accompanied by an enthalpy change of about $0.60 \mathrm{~kJ} \mathrm{~mol}^{-1}$, whereas the conversion of $\alpha$-graphite to diamond has an enthalpy change of about $1.90 \mathrm{~kJ} \mathrm{~mol}^{-1}$. Although neither enthalpy change is very large, it is much easier to transform $\alpha$-graphite to the $\beta$ form than it is to convert it to diamond. Explain this difference.