Metal compound $A$ reacts with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride.
$\underset{\begin{smallmatrix}
\text{Calcium} \\
\text{carbonate}
\end{smallmatrix}}{\mathop{CaC{{O}_{3(s)\,}}}}\,+\,\underset{Hydrochloricacid}{\mathop{2HCl}}\,\,\to $$\underset{Calcium\text{ }chloride\text{ }}{\mathop{CaC{{l}_{2(aq)}}}}\,\,+\,\underset{Carbon\text{ }dioxide}{\mathop{C{{O}_{2(g)}}}}\,$$\mathop { + {H_2}{O_{(l)}}}\limits_{water} $
Write word equations and then balanced equations for the reaction taking place when -
$(a)$ dilute sulphuric acid reacts with zinc granules.
$(b)$ dilute hydrochloric acid reacts with magnesium ribbon.
How is the concentration of hydroxide ions $(OH^-)$ affected when excess base is dissolved in a solution of sodium hydroxide ?
Five solutions $A,\,B,\,C,\,D$ and $E$ when tested with universal indicator showed $pH$ as $4,\,1,\,11,\,7$ and $9$, respectively. Which solution is
$(a)$ neutral ?
$(b)$ strongly alkaline ?
$(c)$ strongly acidic ?
$(d)$ weakly acidic ?
$(e)$ weakly alkaline ?
Arrange the $pH$ in increasing order of hydrogen-ion concentration.
What will happen if a solution of sodium hydrocarbonate is heated ? Give the equation of the reaction involved.
A milkman adds a very small amount of baking soda to fresh milk.
$(a)$ Why does he shift the $pH$ of the fresh milk from $6$ to slightly alkaline ?
$(b)$ Why does this milk take a long time to set as curd ?