Consider separate solution of 0.500 M C₂H₅OH (aq), 0.100 M Mg₃(PO₄)₂ (aq) 0.250 M KBr (aq) and 0.125 M Na₃PO₄ (aq) at 25^oC. Which statement is true about these solutions, assuming all salts to be strong electrolytes?

• They all have the same osmotic pressure

• 0.100 M Mg₃(PO₄)₂ (aq) has the highest osmotic pressure

• 0.125 M Na₃P_O (aq) has the highest osmotic pressure

• 0.125 M Na₃P_O (aq) has the highest osmotic pressure

282.

The ratio of masses of oxygen and nitrogen of a particular gaseous mixture is 1:4. The ratio of number of their molecule is

• 1:4

• 7:32

• 1:8

• 1:8

The molarity of a solution obtained by mixing 750 mL of 0.5 (M) HCl with 250 mL of 2(M) HCl will be

• 0.875 M

• 1.00 M

• 1.75 M

• 1.75 M

The density of a solution prepared by dissolving 120 g of urea (mol. Mass = 60 u ) in 1000g of water is 1.15 g/mL. The molarity of this solution is

• 0.50 M

• 1.78 M

• 1.02 M

• 1.02 M

K_f for water is 1.86K kg mol–1.If your automobile radiator holds 1.0 kg of water, how many grams of ethylene glycol (C₂H₆O₂) must you add to get the freezing point of the solution lowered to –2.8°C?

• 72 g

• 93 g

• 39 g

• 39 g

A 5.2 molal aqueous solution of methyl alcohol, CH₃OH, is supplied. What is the mole fraction of methyl alcohol in the solution?

• 0.100

• 0.190

• 0.086 

• 0.086 

Ethylene glycol is used as an antifreeze in a cold climate. Mass of ethylene glycol which should be added to 4 kg of water to prevent it form freezing at - 6° C will be : (K_f for water = 1.86 K kg mol^-1, and molar mass of ethylene glycol = 62g mol^-1)

• 804.32 g

• 204.30 g 

• 400.00 g

• 400.00 g

A vessel at 1000 K contains CO₂ with a pressure of 0.5 atm. Some of the CO₂ is converted into CO on the addition of graphite. If the total pressure at equilibrium is 0.8 atm, the value of K is

• 1.8 atm

• 3 atm

• 0.3 atm

• 0.3 atm

In the context of the lanthanoids, which of the following statement is not correct?

• There is a gradual decrease in the radii of the members with increasing atomic number in the series. 

• All the member exhibit +3 oxidation state.

• Because of similar properties, the separation of lanthanoids is not easy.

• Because of similar properties, the separation of lanthanoids is not easy.

If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water (ΔT_f), when 0.01 mol of sodium sulphate is dissolved in 1 kg of water, is (K_f = 1.86 K kg mol^–1).

• 0.0372 K

• 0.0558 K

• 0.0744 K

• 0.0744 K