Give the chemical name and formula of:
$(i)$ Soda ash
$(ii)$ Blue vitriol
$(iii)$ Baking soda

Equal lengths of magnesium ribbon are taken in two test tubes $A$ and $B$. $H_{2}SO_{4}$ is added to test tube $A$ and $H_{2}CO_{3}$ in test tube $B$ in equal amounts.
$(a)$ Identify the test tube showing vigorous reaction.
$(b)$ Give reason to support your answer.
$(c)$ Name the gas liberated in both the test tubes. How will you prove its liberation?

Name the gas which is liberated when an acid reacts with a metal. Illustrate with an example. How will you test the presence of this gas?

What is the chemical formula of gypsum?

What happens to the $pH$ of a basic aqueous solution if the concentration of $[OH^-]$ ions increases?

Complete and balance the following chemical equations:
$(a)$ $Ca(OH)_{2} + Cl_{2} \longrightarrow$
$(b)$ $CaSO_{4} \cdot 1/2 H_{2}O + H_{2}O \longrightarrow$
$(c)$ $Na_{2}CO_{3} \cdot 10H_{2}O \xrightarrow{\text{air}} \dots$