$1 \text{ mole}$ of concentrated $HCl$ requires $X \text{ moles}$ of dilute $NaOH$ for neutralization,and $1 \text{ mole}$ of concentrated $H_2SO_4$ requires $Y \text{ moles}$ of dilute $NaOH$. Which of the following relations is true?

$A$ mixture of $CaCl_2$ and $NaCl$ weighing $4.44 \ g$ is treated with sodium carbonate solution to precipitate all the calcium ions as calcium carbonate. The calcium carbonate so obtained is heated strongly to get $0.56 \ g$ of $CaO$. The percentage of $NaCl$ in the mixture is (atomic mass of $Ca=40$)

$A$ mixture of gases contains $H_2$ and $O_2$ gases in the ratio of $1 : 4$ $(w/w)$. What is the molar ratio of the two gases in the mixture?

$4.0 \,g$ of $NaOH$ are contained in one decilitre of solution. Its molarity would be ......... $M$.

For the following reaction,the mass of water produced from $445 \ g$ of $C_{57}H_{110}O_6$ is .............. $g$.
$2C_{57}H_{110}O_{6(s)} + 163O_{2(g)} \to 114CO_{2(g)} + 110H_2O_{(l)}$

Phosphoric acid $(H_3PO_4)$ is a tribasic acid,and one of its salts is sodium dihydrogen phosphate $(NaH_2PO_4)$. What volume of $1 \, M \, NaOH$ solution (in $mL$) must be added to $12 \, g$ of sodium dihydrogen phosphate (molar mass $= 120 \, g/mol$) to convert it into trisodium phosphate $(Na_3PO_4)$?