Calculate the amount of $NO_2$ required for producing $4$ moles of $HNO_3$ as per the chemical reaction,$3 NO_2 + H_2O \longrightarrow 2 HNO_3 + NO$. (in $g$)

What is the value of $w$ (mass of solute in grams) required to prepare a definite volume of a standard solution of known normality $(N)$?
[$N = \text{normality}$,$E = \text{equivalent weight}$,$V = \text{volume of solution in } mL$]

$12 \ g$ of $Mg$ (atomic mass $24$) will react completely with acid to give:

According to the reaction $6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$,how many molecules of $CO_2$ are required to obtain $1.8 \ g$ of glucose? (Molar mass of $C_6H_{12}O_6 = 180 \ g \ mol^{-1}$) $(C = 12, H = 1, O = 16)$

The number of molecules of $CO_2$ liberated by the complete combustion of $0.1 \ mol$ of graphite in air is

How many moles of methane are required to produce $22 \ g$ of $CO_2 \ (g)$ after combustion (in $mol$)?