The physiological reactions occurring in the human body take place in the range of $......\,pH.$

$500 \ ml$ aqueous solution is prepared by dissolving $2$ moles of $HCl$ in water. What will be the molarity of this solution (in $M$)?

Match the acids given in Column $(A)$ with their correct source given in Column $(B)$.

Column $(A)$	Column $(B)$
$(a)$ Lactic acid	$(i)$ Tomato
$(b)$ Acetic acid	$(ii)$ Lemon
$(c)$ Citric acid	$(iii)$ Vinegar
$(d)$ Oxalic acid	$(iv)$ Curd

In a basic aqueous solution,what happens to the basicity of the solution as the concentration of $[OH^-]$ increases?

Which of the following statements is true for acids?

Common salt, besides being used in the kitchen, can also be used as the raw material for making:
$(i)$ Washing soda
$(ii)$ Bleaching powder
$(iii)$ Baking soda
$(iv)$ Slaked lime