Equal masses of oxygen and ozone are present in a container at 298 K. The ratio of their partial pressures ($P_{O_2} : P_{O_3}$) is:

A mixture of $2.3$ g formic acid and $4.5$ g oxalic acid is treated with conc. $H_2SO_4$. The evolved gaseous mixture is passed through $KOH$ pellets. The weight (in g) of the remaining product at STP will be

A 0.50 $M$ solution of $KI$ reacts with excess of ${{\rm{H}}_2}{\rm{S}}{{\rm{O}}_4}$ and ${\rm{KI}}{{\rm{O}}_3}$ solutions according to the equation, $6{{\rm{H}}^ + } + 5{{\rm{I}}^ - } + {\rm{IO}}_3^ - o 3{{\rm{I}}_2} + 3{{\rm{H}}_2}{\rm{O}}$. Which of the following statements is true?

0.3 g of an oxalate salt was dissolved in 100 mL solution. The solution required 90 mL of $N/20$ ${\rm{KMn}}{{\rm{O}}_4}$ for complete oxidation. The % of oxalate ion in salt is:

A mixture of ${\rm{2}}{\rm{.3}}\,\,{\rm{g}}$ formic acid and ${\rm{4}}{\rm{.5}}\,\,{\rm{g}}$ oxalic acid is treated with conc. ${{\rm{H}}_{{\rm{2}}\,}}{\rm{S}}{{\rm{o}}_{\rm{4}}}$ . The evolved gaseous mixture is passed through ${\rm{KOH}}$ pellets weight (in g) of the remaining product at STP will be

25.0 g of a calcium carbonate sample decomposes on heating to give carbon dioxide and 10.0 g calcium oxide. What will be the percentage purity of calcium carbonate in the sample? (Atomic weight: $Ca = 40$)

How many moles of water are present in 22.4 L of water vapor at Standard Temperature and Pressure (STP)?

Elements X and Y form compounds $XY_2$ and $X_3Y_2$. If 20 g of $XY_2$ contains 0.2 moles and 18 g of $X_3Y_2$ contains 0.1 moles. What are the atomic weights of elements X and Y?

According to the Haber-Bosch process, the molar ratio of hydrogen to ammonia is:

In the Haber process, if 40 moles of ammonia are formed, the number of moles of hydrogen consumed is?

Which of the following contains the largest number of water molecules?