Discuss the role of pH in causes of tooth decay.

Define $\mathrm{pH}$. Which of the following salts will have $\mathrm{pH}$ more than 7?

(i) Zinc sulphate (ii) Sodium acetate (iii) Potassium nitrate

Complete the following reaction:

$\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\left(\mathrm{aq}\right)+\mathrm{\_\_\_\_\_}\to {\mathrm{CaCO}}_3\left(\mathrm{s}\right)+\mathrm{\_\_\_\_\_}$

Complete the following reaction:

Sodium hydrogen carbonate $+$ _____ $\to$Sodium chloride $+$ _____ $+$ _____

Complete the following reaction:

Aluminium $+$Sulphuric acid $\to$_____ $+$ _____

Comment on the following:

All alkalis are bases but all bases are not alkalies.