Carbon and oxygen form two oxides, carbon monoxide and carbon dioxide, where the weight ratios of carbon to oxygen are 12:16 and 12:32, respectively. These ratios demonstrate:

1. Law of multiple proportions

2. Law of reciprocal proportions

3. Law of conservation of mass

4. Law of constant proportions

The formula of an acid is ${\mathrm{HXO}}_2.$ The mass of 0.0242 moles of the acid is 1.657 g.
The atomic weight of X is:

A 6.85 g sample of the hydrates $\mathrm{Sr}{\left(\mathrm{OH}\right)}_2.{\mathrm{xH}}_2\mathrm{O}$ is dried in an oven to give 3.13 g of anhydrous $\mathrm{Sr}{\left(\mathrm{OH}\right)}_2$. The value of x is - 

(Atomic weights : Sr=87.60, O=16.0, H=1.0)

1.  8

2.  12

3.  10

4.  6

A sample of phosphorus that weights 12.4 g exerts a pressure 8 atm in a 0.821 litre closed vessel at 527$°$C. The molecular formula of the phosphorus vapour is:

1.  ${\mathrm{P}}_2$

2.  ${\mathrm{P}}_4$

3.  ${\mathrm{P}}_6$

4.  ${\mathrm{P}}_8$

Sulphur burns according to the reaction

 $\frac{1}{8}{\mathrm{S}}_8\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)$ $\stackrel{}{\to }$ ${\mathrm{SO}}_2\left(\mathrm{g}\right)$
What volume of air, at 1 atm and 273 K, containing 21%  oxygen by volume is required to completely burn sulphur $\left({\mathrm{S}}_8\right)$ present in 200 g of the sample?
(This sample contains 20% inert material which does not burn)

1.  23.52 litre

2.  320 litre

3.  112 litre

4.  533.33 litre

Phosphoric acid $\left({\mathrm{H}}_3{\mathrm{PO}}_4\right)$ prepared in a two step process.

(1) ${\mathrm{P}}_4+5{\mathrm{O}}_2 \stackrel{}{\to } {\mathrm{P}}_4{\mathrm{O}}_{10}$
(2) ${\mathrm{P}}_4{\mathrm{O}}_{10}+6{\mathrm{H}}_2\mathrm{O} \stackrel{}{\to } 4{\mathrm{H}}_3{\mathrm{PO}}_4$

We allow 62g of phosphorus to react with react with excess oxygen which form ${\mathrm{P}}_4{\mathrm{O}}_{10}$ in 85% yield. In the step (2) reaction 90% yield of ${\mathrm{H}}_3{\mathrm{PO}}_4$ is obtained. Produced mass of ${\mathrm{H}}_3{\mathrm{PO}}_4$ is:

1.  37.485 g

2.  149.949 g

3.  125.47 g

4.  564.48 g

100 mL of ${\mathrm{H}}_2{\mathrm{SO}}_4$ solution having molarity of 1M and density 1.5 g/mL is mixed with 400 mL of water. The molarity of the ${\mathrm{H}}_2{\mathrm{SO}}_4$ solution will be: (final density is 1.25 g/mL )

What volume of HCl solution of density 1.2 g/cm³ and containing 36.5% by weight HCl, must be allowed to react with zinc(Zn) in order to liberate 4.0 g of hydrogen?

1.  333.33 mL

2.  500 mL

3.  614.66 mL

4.  None of these

The molar mass of diacidic organic Lewis base (B), if 12 g of chloroplatinate salt $\left({\mathrm{BH}}_2{\mathrm{PtCl}}_6\right)$ on ignition produced 5 gm residue of Pt,will be -

1.  52

2.  58

3.  88

4.  None of these

Equivalent weight of ${\mathrm{FeS}}_2$ in the half reaction, ${\mathrm{FeS}}_2 \stackrel{}{\to } {\mathrm{Fe}}_2{\mathrm{O}}_3+{\mathrm{SO}}_2$ is:

1.  M/10

2.  M/11

3.  M/6

4.  M/1