Write one equation each for decomposition reactions where energy is supplied in the form of heat, light or electricity.
$(a)$ Thermal decomposition :
$\underset{Ferrous\,\,sulphate}{\mathop{2FeS{{O}_{4}}}}\,\,\xrightarrow{\Delta }$$\mathop {F{e_2}{O_{3(s)}}}\limits_{Ferric\,\,\,oxide} \, + \mathop {\,S{O_{2(g)}}}\limits_{Sulphur{\text{ }}dioxide\;} \, + \mathop {\,S{O_{3(g)}}}\limits_{Sulphur{\text{ }}trioxide} $
$(b)$ Decomposition by light :
$2AgC{l_{(s)}}\;\xrightarrow{{{\text{ Light }}}}\mathop {2A{g_{(s)}}}\limits_{Silver} + \mathop {C{l_{2(g)}}}\limits_{Chlorine} $
$(c)$ Decomposition by electricity :
$\mathop {2A{l_2}{O_{3(aq)}}}\limits_{Aluminium{\text{ }}oxide} \xrightarrow{{{\text{ Electricity }}}}\mathop {\;{\kern 1pt} 4A{l_{(s)}}}\limits_{Aluminium} + \mathop {3{O_{2(g)}}}\limits_{Oxygen} $
Explain the ''Rancidity'' terms with one example.
What does one mean by exothermic and endothermic reactions ? Give examples.
Why does the colour of copper sulphate solution change when an iron nail is dipped in it ?
Balance the following chemical equations.
$(a)$ $HNO _{3}+ Ca ( OH )_{2} \longrightarrow Ca \left( NO _{3}\right)_{2}+ H _{2} O$
$(b)$ $NaOH + H _{2} SO _{4} \longrightarrow Na _{2} SO _{4}+ H _{2} O$
$(c)$ $NaCl + AgNO _{3} \longrightarrow AgCl + NaNO _{3}$
$(d)$ $BaCl _{2}+ H _{2} SO _{4} \longrightarrow BaSO _{4}+ HCl$
Write the balanced equation for the following chemical reactions.
$(i)$ Hydrogen $+$ Chlorine $\to $ Hydrogen chloride
$(ii)$ Barium chloride $+$ Aluminium sulphate $\to $ Barium sulphate $+$ Aluminium chloride
$(iii)$ Sodium $+$ Water $\to $ Sodium hydroxide $+$ Hydrogen