How many moles are there in $4.9 \ g$ of $H_{2}SO_{4}$?

State whether the following statement is true or false:
When the $pH$ of rainwater is more than $5.6,$ it is called acid rain.

$pH + pOH = ?$

How is an aqueous solution with $pH$ $12$ compared to an aqueous solution with $pH$ $9$?

How is bleaching powder prepared? Why does bleaching powder $(i)$ smell strongly of chlorine?

$(a)$ If we take hydrochloric acid and acetic acid of the same concentration,which one will produce a lower $H^{+}$ ion concentration? Out of the two,which one is a weak acid?
$(b)$ If someone is suffering from acidity,which of the following would you suggest to cure it: vinegar,orange juice,or baking soda solution? Give a reason for your answer.