Complex A has a composition of H₁₂O₆Cl₃Cr . If the complex on treatment with concentrated H₂SO₄ loses 13.5% of its original mass, the correct molecular formula of A is : 
[ Given: atomic mass of Cr = 52 amu  and Cl =35 amu]

1. [Cr(H₂O)₅Cl]Cl₂$·$H₂O
2. [Cr(H₂O)₆]Cl₃
3. [Cr(H₂O)₃Cl₃]$·$3H₂O
4. [Cr(H₂O)₄Cl₂]Cl$·$2H₂O

The volume, in mL, of 0.02 M K₂Cr₂O₇ solution required to react with 0.288 g of ferrous oxalate in an acidic medium is: 
[Given: Molar mass of Fe = 56 g mol^–1]

1. 55 mL
2. 45 mL
3. 50 mL
4. 60 mL

The formula of a gaseous hydrocarbon which requires 6 times its own volume of O₂ for complete oxidation and produces 4 times its own volume of CO₂ is C_xH_y. The value of y is:

1. 6
2. 8
3. 4
4. 10

1.86 g of aniline completely reacts to form acetanilide. 10% of the product is lost during purification. The amount of acetanilide obtained after purification (in g) is _______ × 10^–2.

1. 248
2. 243
3. 256
4. 262

A solution of two components containing ${\mathrm{n}}_1$ moles of the 1^st component ${\mathrm{n}}_2$ moles of the 2^nd component is prepared. ${\mathrm{M}}_1<mspace\; width="1em"></mspace>\mathrm{and}<mspace\; width="1em"></mspace>{\mathrm{M}}_2$ are the molecular weights of component 1 and 2 respectively. If d is the density of the solution in g ${\mathrm{mL}}^{-1}$, ${\mathrm{C}}_2$ is the molarity and ${\mathrm{x}}_2$ is the mole fraction of the 2^nd component, then ${\mathrm{C}}_2$ can be expressed as: 

1. ${\mathrm{C}}_2=\frac{{\mathrm{dx}}_2}{{\mathrm{M}}_2+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

2. ${\mathrm{C}}_2=\frac{1000<mspace\; width="1em"></mspace>{\mathrm{dx}}_2}{{\mathrm{M}}_1+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

3. ${\mathrm{C}}_2=\frac{1000{\mathrm{x}}_2}{{\mathrm{M}}_1+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

4. ${\mathrm{C}}_2=\frac{{\mathrm{dx}}_1}{{\mathrm{M}}_2+{\mathrm{x}}_2\left({\mathrm{M}}_2-{\mathrm{M}}_1\right)}$

A solution of phenol in chloroform when treated with aqueous NaOH gives compound P as a major product. The mass percentage of carbon in P is:
(to the nearest integer) (Atomic mass : C =12; H=1; O=16)

0.4 g mixture of NaOH, Na₂CO₃ and some inert impurities was first titrated with $\frac{N}{10}$ HCl using phenolphthalein as an indicator, 17.5 mL of HCl was required at the end point. After his methyl orange was added and titrated. 1.5 mL of same HCl was required for the next end point. The weight percentage of Na₂CO₃ in the mixture is- (Rounded-off to the nearest integer)

1. 6 %
2. 4 %
3. 7 %
4. 9 %

1 gram of a carbonate (M₂CO₃) on treatment with excess HCl produces 0.01186 moles of CO₂. The molar mass of M₂CO₃ in g mol^–1 is:

1. 118.6

2. 11.86

3. 88.6

4. 84.3

A gaseous hydrocarbon upon combustion gives 0.72 g of water and 3.08 g. of CO₂. The empirical formula of the hydrocarbon is:

What is the ratio of the number of molecules of oxygen to nitrogen in a specific gaseous mixture if their mass ratio is 1:4?