$50 \ mL$ of $0.5 \ M$ oxalic acid is needed to neutralize $25 \ mL$ of sodium hydroxide solution. The amount in grams of $NaOH$ in $50 \ mL$ of the given sodium hydroxide solution is:

Consider the reaction shown below. The percentage yield of the amide product is $......$ . (Round off to the Nearest Integer). (Given: Atomic mass: $C = 12.0 \, u, H = 1.0 \, u, N = 14.0 \, u, O = 16.0 \, u, Cl = 35.5 \, u$)
$C_6H_5COCl + (C_6H_5)_2NH \rightarrow C_6H_5CON(C_6H_5)_2 + HCl$
Given: $0.140 \, g$ of $C_6H_5COCl$ reacts with $0.388 \, g$ of $(C_6H_5)_2NH$ to produce $0.210 \, g$ of $C_6H_5CON(C_6H_5)_2$.

One litre of a gas at $STP$ weighs $1.16 \ g$. It can possibly be:

One litre oxygen gas at $STP$ will weigh $.................. \ g$

$24 \ g$ of $Mg$ metal reacts with water. How many moles of $H_2$ will be liberated? ............. $mol$

Concentrated $HCl$ is $10 \, N$. How much volume of concentrated $HCl$ is required to prepare $1000 \, mL$ of $1 \, N$ $HCl$ by dilution?