Consider the following reaction:

$2{\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-\mathrm{OH} + 2\mathrm{Na}\to 2{\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-\mathrm{ONa} + {\mathrm{H}}_2$

Compare the structure of the substrate propanol with that of the product sodium propoxide. Which part of the substrate, the carbon skeleton, or the $\mathrm{OH}$ group has undergone a change during the reaction?

Observe the structural formulae (i) and (ii). Find out their molecular formulae. What is the difference between them? What is the relation between the two compounds represented by these structural formulae?

Some bond fissions are described in the following table. For each of them, show the movement of electrons using curved arrow notation. Classify them as homolysis or heterolysis and identify the intermediate species produced as carbocation, carbanion or free radical.

Identify the 'reagent', 'substrate', 'product', and 'by-product' in the following reaction.

${\mathrm{CH}}_3\mathrm{COCl}+{\mathrm{NH}}_3\to {\mathrm{CH}}_3{\mathrm{CONH}}_2+\mathrm{HCl}$

How is covalent bond formed between two atoms?

Consider two covalently bonded atoms $\mathrm{Q}$ and $\mathrm{R}$ where $\mathrm{R}$ is more electronegative than $\mathrm{Q}$. Will these atoms share the electron pair equally between them?

Consider two covalently bonded atoms $\mathrm{Q}$ and $\mathrm{R}$ where $\mathrm{R}$ is more electronegative than $\mathrm{Q}$. Represent the polar covalent bond between $\mathrm{Q}$ and $\mathrm{R}$ using fractional charges ${\mathrm{\delta }}^{\oplus }$ and ${\mathrm{\delta }}^{⊝}$.