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A 6% solution of urea is isotonic with :

• 1M solution of glucose

• 0.05 M solution of glucose

• 6% solution of glucose

• 25% solution of glucose

For a chemical reaction A $\to$ B, the rate of the reaction is 2x10^-3 mol dm^-3 s^-1 , when the initial concentration is 0.05 mol dm^-3 . The rate of the same reaction is 1.6 x 10^-2 mol dm^-3 s^-1 , when the initial concentration is 0.1 mol dm^-3 .The order of the reaction is :

• 2

• 0

• 3

• 1

The temperature of the slag zone in metallurgy of iron using blast furnace is :

• 1200-1500°C

• 1500-1600°C

• 400-700°C

• 800-1000°C

In countries nearer to polar region, the roads are sprinkled with CaCl₂ .This is :

• to minimise the wear and tear of the roads

• to minimise the snow fall

• to minimise pollution

• to minimise the accumulation of dust on the road

The solubility of a gas in water at 300 K under a pressure of 100 atm is 4 x 10^-3 kg L^-1. Therefore, the mass of the gas in kg dissolved 250 mL of water under a pressure of 250 atm at 300 K is :

• 2.5 x 10^-3

• 2.0 x 10^-3

• 1.25 x 10^-3

• 5.0 x 10^-3

An aqueous solution containing 6.5 g of NaCl of 90 purity was subjected to electrolysis. After the complete electrolysis, the solution was evaporated to get solid NaOH. The volume of 1 M acetic acid required to neutralise NaOH obtained above is :

• 1000 cm³

• 2000 cm³

• 100 cm³

• 200 cm³

Corrosion of iron is essentially an electrochemical phenomenon where the cell reactions are :

• Fe is oxidised to Fe²⁺ and dissolved oxygen in water is reduced to OH^-

• Fe is oxidised to Fe³⁺ and H₂O is reduced to ${\mathrm{O}}_2^{2-}$

• Fe is oxidised to Fe²⁺ and H₂O is reduced to ${\mathrm{O}}_2^{2-}$

• Fe is oxidised to Fe²⁺ and H₂O is reduced to O₂

When plants and animals decay, the organic nitrogen is converted into inorganic nitrogen. The inorganic nitrogen is in the form of :

• ammonia

• elements of nitrogen

• nitrates

• nitrides

Among the oxides, Mn₂O₇ (I) , V₂O₃ (II) , V₂O₅ (III) , CrO (IV) , Cr₂O₃ (V) the basic oxides are :

• I and II

• II and III

• III and IV

• II and IV

A emulsifier is a substance which :

• stabilises the emulsion

• homogenises the emulsion

• coagulates the emulsion

• accelerates the dispersion of liquid in liquid