The formula of a metallic oxide is $MO$. What will be the formula of its phosphate?

$25 \ cm^3$ of oxalic acid completely neutralized $0.064 \ g$ of sodium hydroxide. The molarity of the oxalic acid solution is: (in $M$)

How many grams of a dibasic acid (molar mass = $200 \ g/mol$) are present in $100 \ mL$ of its $0.1 \ N$ aqueous solution (in $g$)?

If the enthalpy of combustion of anhydrous oxalic acid is $x \, kcal \, mol^{-1}$,then how much heat in $kcal$ will be produced by the combustion of $2 \, g$ of oxalic acid?

$A$ solution $(5 \, mL)$ of an acid $X$ is completely neutralized by $y \, mL$ of $1 \, M \, NaOH$. The same volume $(y \, mL)$ of $1 \, M \, NaOH$ is required to neutralize $10 \, mL$ of $0.6 \, M \, H_2SO_4$ completely. The normality $(N)$ of the acid $X$ is $......$

Galena (an ore) is partially oxidized by passing air through it at high temperature. After some time,the passage of air is stopped,but the heating is continued in a closed furnace such that the contents undergo self-reduction. The weight (in $kg$) of $Pb$ produced per $kg$ of $O_2$ consumed is $. . . . .$ (Atomic weights in $g \ mol^{-1}: O = 16, S = 32, Pb = 207$)