Explain the "Oxidation'' in terms of gain or loss of oxygen with two examples.
Oxidation is the gain of oxygen.
For example :
$(i)$ $C{O_2}\, + \,\mathop {{H_2}\, \to \,CO\, + \,{H_2}O}\limits_{Addition\,of\,oxygen\, - \,oxidation} $
$(ii)$ $\mathop {2Cu\, + {O_2}\, \to \,2CuO}\limits_{Gain\,of\,oxygen\,- \,Oxidation} $
In equation $(i)$, $H_2$ is oxidized to $H_2O$ and in equation $(ii)$, $Cu$ is oxidised to $CuO$.
In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.
Why is respiration considered an exothermic reaction ? Explain.
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
Balance the following chemical equations.
$(a)$ $HNO _{3}+ Ca ( OH )_{2} \longrightarrow Ca \left( NO _{3}\right)_{2}+ H _{2} O$
$(b)$ $NaOH + H _{2} SO _{4} \longrightarrow Na _{2} SO _{4}+ H _{2} O$
$(c)$ $NaCl + AgNO _{3} \longrightarrow AgCl + NaNO _{3}$
$(d)$ $BaCl _{2}+ H _{2} SO _{4} \longrightarrow BaSO _{4}+ HCl$
Why is the amount of gas collected in one of the test tubes in image double of the amount collected in the other ? Name this gas.