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The elemental composition of a compound is \( 54.2\% \) C, \( 9.2\% \) H and \( 36.6\% \) O. If the molar mass of the compound is \( 132 \, \text{g mol}^{-1} \), the molecular formula of the compound is:
[Given: The relative atomic mass of \( \text{C} : \text{H} : \text{O} = 12 : 1 : 16 \)]

\( 10 \, \text{mL} \) of \( 2 \, \text{M} \) NaOH solution is added to \( 20 \, \text{mL} \) of \( 1 \, \text{M} \) HCl solution kept in a beaker. Now, \( 10 \, \text{mL} \) of this mixture is poured into a volumetric flask of \( 100 \, \text{mL} \) containing \( 2 \) moles of HCl and made the volume upto the mark with distilled water. The solution in this flask is:

Some \( \mathrm{CO_2} \) gas was kept in a sealed container at a pressure of \( 1 \,\text{atm} \) and at \( 273 \,\text{K} \). This entire amount of \( \mathrm{CO_2} \) gas was later passed through an aqueous solution of \( \mathrm{Ca(OH)_2} \). The excess unreacted \( \mathrm{Ca(OH)_2} \) was later neutralized with \( 0.1 \,\text{M} \) of \( 40 \,\text{mL} \) HCl. If the volume of the sealed container of \( \mathrm{CO_2} \) was \( x \), then \( x \) is _____________ \( \text{cm}^3 \) (nearest integer).
[Given: The entire amount of \( \mathrm{CO_2(g)} \) reacted with exactly half the initial amount of \( \mathrm{Ca(OH)_2} \) present in the aqueous solution.]

On complete combustion \( 1.0 \, \mathrm{g} \) of an organic compound \( (X) \) gave \( 1.46 \, \mathrm{g} \) of \( \mathrm{CO_2} \) and \( 0.567 \, \mathrm{g} \) of \( \mathrm{H_2O} \). The empirical formula mass of compound \( (X) \) is ______ \( \mathrm{g} \).
(Given molar mass in \( \mathrm{g \, mol^{-1}} \) \( \mathrm{C:} \, 12 \), \( \mathrm{H:} \, 1 \), \( \mathrm{O:} \, 16 \))

\( 20 \, \text{mL} \) of sodium iodide solution gave \( 4.74 \, \text{g} \) silver iodide when treated with excess of silver nitrate solution. The molarity of the sodium iodide solution is ______ \( \text{M} \). (Nearest integer value)
[Given: \( \mathrm{Na} = 23 \), \( \mathrm{I} = 127 \), \( \mathrm{Ag} = 108 \), \( \mathrm{N} = 14 \), \( \mathrm{O} = 16 \, \text{g mol}^{-1} \)]

The molar mass of the water insoluble product formed from the fusion of chromite ore \( \mathrm{(FeCr_2O_4)} \) with \( \mathrm{Na_2CO_3} \) in presence of \( \mathrm{O_2} \) is ________ \( \mathrm{g \, mol^{-1}} \).

Fortification of food with iron is done using \( \mathrm{FeSO}_{4}\cdot7\mathrm{H}_{2}\mathrm{O} \). The mass in grams of the \( \mathrm{FeSO}_{4}\cdot7\mathrm{H}_{2}\mathrm{O} \) required to achieve \( 12 \,\text{ppm} \) of iron in \( 150 \,\text{kg} \) of wheat is ______ (Nearest integer) [Given: Molar mass of Fe, S and O respectively are \( 56 \), \( 32 \) and \( 16 \,\mathrm{g\, mol^{-1}} \)]

\( \mathrm{CaCO_3(s) + 2HCl(aq) \rightarrow CaCl_2(aq) + CO_2(g) + H_2O(l)} \)
Consider the above reaction, what mass of \( \mathrm{CaCl_2} \) will be formed if \( 250 \, \mathrm{mL} \) of \( 0.76 \, \mathrm{M} \) HCl reacts with \( 1000 \, \mathrm{g} \) of \( \mathrm{CaCO_3} \)?
(Given : Molar mass of Ca, C, O, H and Cl are \( 40 \), \( 12 \), \( 16 \), \( 1 \) and \( 35.5 \, \mathrm{g \, mol^{-1}} \), respectively)

Consider the following reaction occurring in the blast furnace:
\( \mathrm{Fe_3O_4 (s) + 4\,CO (g) \rightarrow 3\,Fe (l) + 4\,CO_2 (g)} \)
\( 'x' \) \( \mathrm{kg} \) of iron is produced when \( 2.32 \times 10^{3} \; \mathrm{kg} \; \mathrm{Fe_3O_4} \) and \( 2.8 \times 10^{2} \; \mathrm{kg} \; \mathrm{CO} \) are bought together in the furnace. The value of \( 'x' \) is _______ . (nearest integer)
\( \{ \text{Given: molar mass of } \mathrm{Fe_3O_4} = 232 \; \mathrm{g\,mol^{-1}} \} \)
molar mass of \( \mathrm{CO} = 28 \; \mathrm{g\,mol^{-1}} \)
molar mass of \( \mathrm{Fe} = 56 \; \mathrm{g\,mol^{-1}} \)

On combustion \( 0.210 \, \text{g} \) of an organic compound containing \( \mathrm{C} \), \( \mathrm{H} \) and \( \mathrm{O} \) gave \( 0.127 \, \text{g} \) \( \mathrm{H_2O} \) and \( 0.307 \, \text{g} \) \( \mathrm{CO_2} \). The percentages of hydrogen and oxygen in the given organic compound respectively are:

Butane reacts with oxygen to produce carbon dioxide and water following the equation given below.
\( \mathrm{C_4H_{10}(g)} + \frac{13}{2}\mathrm{O_2(g)} \rightarrow 4\mathrm{CO_2(g)} + 5\mathrm{H_2O(l)} \)
If \( 174.0 \, \mathrm{kg} \) of butane is mixed with \( 320.0 \, \mathrm{kg} \) of \( \mathrm{O_2} \) the volume of water formed in liters is _____. (Nearest integer)
[Given: (a) Molar mass of \( \mathrm{C, H, O} \) are \( 12, 1, 16 \, \mathrm{g \, mol^{-1}} \) respectively, (b) Density of water \( = 1 \, \mathrm{g \, mL^{-1}} \)]

Quantitative analysis of an organic compound (X) shows following \( \% \) composition. C : \( 14.5\% \) Cl : \( 64.46\% \) H : \( 1.8\% \)
(Empirical formula mass of the compound (X) is ______ \( \times 10^{-1} \) )
[Given molar mass in \( \mathrm{g\, mol^{-1}} \) of C : \( 12 \) , H : \( 1 \) , O : \( 16 \) , Cl : \( 35.5 \)]

Concentrated nitric acid is labelled as \( 75\% \) by mass. The volume in \( \text{mL} \) of the solution which contains \( 30 \, \text{g} \) of nitric acid is ____________.
Given: Density of nitric acid solution is \( 1.25 \, \text{g/mL} \).

The molarity of a \( 70\% \) (mass/mass) aqueous solution of a monobasic acid (X) is ______ \( \times 10^{-1} \) \( \mathrm{M} \). (Nearest integer)
[Given: Density of aqueous solution of (X) is \( 1.25 \, \mathrm{g\, mL^{-1}} \). Molar mass of the acid is \( 70 \, \mathrm{g\, mol^{-1}} \)]

The d-electronic configuration of an octahedral Co(II) complex having magnetic moment of \( 3.95 \ \text{BM} \) is:

\( 0.1 \) mol of the following given antiviral compound \( (\mathrm{P}) \) will weigh __________ \( \times 10^{-1} \, \mathrm{g} \) (nearest integer).

\( \text{(Given : molar mass in g mol}^{-1}\text{ ) } \mathrm{H}:1 , \mathrm{C}:12 , \mathrm{N}:14 , \mathrm{O}:16 , \mathrm{F}:19 , \mathrm{I}:127 \)

\( 0.5 \,\text{g} \) of an organic compound on combustion gave \( 1.46 \,\text{g} \) of \( \text{CO}_2 \) and \( 0.9 \,\text{g} \) of \( \text{H}_2\text{O} \). The percentage of carbon in the compound is __________. (Nearest integer) [Given: Molar mass (in \( \text{g mol}^{-1} \)) \( \text{C} : 12 \) ; \( \text{H} : 1 \) ; \( \text{O} : 16 \)]

Mass of magnesium required to produce \( 220 \, \text{mL} \) of hydrogen gas at \( \text{STP} \) on reaction with excess of dil. \( \mathrm{HCl} \) is:
Given: Molar mass of \( \mathrm{Mg} \) is \( 24 \, \text{g mol}^{-1} \).

Choose the correct statements.
(A) Weight of a substance is the amount of matter present in it.
(B) Mass is the force exerted by gravity on an object.
(C) Volume is the amount of space occupied by a substance.
(D) Temperatures below $0\,^{\circ}\text{C}$ are possible in Celsius scale, but in Kelvin scale negative temperature is not possible.
(E) Precision refers to the closeness of various measurements for the same quantity.
Choose the correct answer from the options given below:

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JEE Main 2025 3rd April Evening Shift

Mass of magnesium required to produce \( 220 \, \text{mL} \) of hydrogen gas at \( \text{STP} \) on reaction with excess of dil. \( \mathrm{HCl} \) is:
Given: Molar mass of \( \mathrm{Mg} \) is \( 24 \, \text{g mol}^{-1} \).