Question

The arrow pointing downwards ($\downarrow$) shows the evolution of gas during a chemical reaction.

• A. True
• B. False

Answer 1

The correct option is B False

• The arrow pointing downwards ($\downarrow$) shows the formation of precipitates during a chemical reaction.
• $$\begin{gathered} {\mathrm{Na}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)+{\mathrm{BaCl}}_2\left(\mathrm{aq}\right)\to {\mathrm{BaSO}}_4(\downarrow )+2\mathrm{NaCl}\left(\mathrm{aq}\right) \\ (\mathrm{Sodium}\mathrm{sulphate})(\mathrm{Barium}\mathrm{chloride})(\mathrm{Barium}\mathrm{sulphate})(\mathrm{Sodium}\mathrm{chloride}) \end{gathered}$$
• Here, the precipitate of Barium sulphate is shown in the form of a downward arrow.
• The arrow pointing downwards ($\uparrow$) shows the evolution of gas during a chemical reaction.
• $$\begin{gathered} {\mathrm{CaCO}}_3\to \mathrm{CaO}+{\mathrm{CO}}_2(\uparrow ) \\ (\mathrm{Calcium}\mathrm{carbonate})(\mathrm{Calcium}\mathrm{oxide})(\mathrm{Carbon}\mathrm{dioxide}) \end{gathered}$$
• Here, the liberation of Carbon dioxide gas is indicated in the form of an upward pointing arrow.

Therefore, the given statement is false.