At 25°C, at 5% aqueous solution of glucose (molecular weight = 180g mol^-1) is isotonic with a 2% aqueous solution containing and unknown solute. What is the molecular weight of the unknown solute?

• 60

• 80

• 72

• 63

200 mL of water is added to a 500 mL of 0.2 M solution. What is the molarity of this diluted solution?

• 0.5010M

• 0.2897M

• 0.7093

• 0.1428

Which of the following pairs of substances would give same gaseous product on reaction with water?

• Na and Na₂O₂

• Ca and CaH₂

• Ca and CaO

• Ba and BaO₂

When 200 mL of aqueous solution of HCl (pH = 2) is mixed with 300 mL of an aqueous solution of NaOH (pH = 12) the pH of the resulting mixture is

• 10

• 2.7

• 4.0

• 11.3

In acid medium, Zn reduces nitrate ion to NH${}_4^{+}$ ion according to the reaction,

Zn + NO${}_3^{-}$→ Zn²⁺ + NH${}_4^{+}$ + H₂O (unbalanced).

How many moles of HCl are required to reduce half a mole of NaNO₃ completely ? Assume the availability of sufficient Zn.

• 5

• 4

• 3

• 2

86.

The percentage of an element M is 53 in its oxide of molecular formula M₂O₃. Its atomic mass is about

• 45

• 9

• 27

• 36

The relative lowering of vapour pressure of a dilute aqueous solution containing non-volatile solute is 0.0125. The molality of the solution is about

• 0.70

• 0.50

• 0.90

• 0.80

The pH of a solution obtained by mixing 50 mL of 1 N HCl and 30 mL of 1 N NaOH is [log 2.5 = 0.3979]

• 12.042

• 0.6021

• 0.3979

• 3.979

0.1 mole of a carbohydrate with empirical formula CH₂O contains 1 g of hydrogen. What is its molecular formula?

• C₂H₄O₂

• C₅H₁₀O₅

• C₃H₆O₃

• C₆H₁₂O₆

How much of sulphur is present in an organic compound, if 0.53 g of the compound gave 1.158 g of BaSO₄ on analysis ? 

• 10%

• 20%

• 30%

• 15%