If $50 \ mL$ of $0.5 \ M$ oxalic acid is required to neutralize $25 \ mL$ of $NaOH$ solution, the amount of $NaOH$ in $50 \ mL$ of the given $NaOH$ solution is . . . . . . $g$.

When excess $CO_2$ is passed through a solution containing $0.205 \ mol$ of $BaCO_3$,what is the mass of $Ba(HCO_3)_2$ formed in grams?

$0.1 \ M$ solution of $KI$ reacts with excess of $H_2SO_4$ and $KIO_3$ solution. According to the equation $5I^{-} + IO_3^{-} + 6H^{+} \rightarrow 3I_2 + 3H_2O$. Identify the correct statements $:$
$(A)$ $200 \ mL$ of $KI$ solution reacts with $0.004 \ mol$ of $KIO_3$.
$(B)$ $200 \ mL$ of $KI$ solution reacts with $0.006 \ mol$ of $H_2SO_4$.
$(C)$ $0.5 \ L$ of $KI$ solution produced $0.005 \ mol$ of $I_2$.
$(D)$ Equivalent weight of $KIO_3$ is equal to $\frac{\text{Molecular weight}}{5}$.
Choose the correct answer from the options given below $:$

When oxygen is heated in the presence of a catalyst,$15 \%$ of it is converted into ozone. How many grams of oxygen are required to produce $33.6 \, L$ of $O_3$ at $STP$?

Which of the following reactions exhibits good atom economy according to the principles of green chemistry?

Consider the complete combustion of butane. The amount of butane utilized to produce $72.0 \ g$ of water is $.... \times 10^{-1} \ g$ (in nearest integer).