Recent questions in Chemistry

To $500cm^3$ of water $3.0\times 10^{-3}$kg of acetic acid is added .If 2.3% of acetic acid is dissociated.What will be the depression of freezing point?$K_f$ and density of water are $1.86$K kg/mol and $0.997g/cm^3$ respectively.

asked Aug 6, 2014 by sreemathi.v

1 answer

The freezing point of a solution containing 0.2g of acetic acid in 20.0g benzene is lowered by $0.45^{\large\circ}$C.Calculate the degree of association of acetic acid in benzene.Assume acetic acid dimerises in benzene.$K_f$ for benzene =$5.12Kmol^{-1}Kg$

asked Aug 6, 2014 by sreemathi.v

1 answer

If boiling point of an aqueous solution is 100.1$^{\large\circ}C$,what is its freezing point.Given,latent heat of fusion and vaporization of water as $80cal g^{-1}$ and $540cal g^{-1}$ respectively.

asked Aug 6, 2014 by sreemathi.v

1 answer

A very small amount of a non-volatile solute (that does not dissociate) is dissolved in $56.8cm^3$ of benzene (density $=0.889gcm^{-3}$).At room temperature vapour pressure of this solution is 98.88mm Hg while that of benzene is 100 mm Hg.Find the molality of this solution.If the freezing temperature of this solution is 0.73 degree lower than that of benzene .What is the value of $K_f$ for benzene?

asked Aug 6, 2014 by sreemathi.v

1 answer

Find the molality of a solution containing a non-volatile solute if the vapour pressure is 2% below the vapour pressure of pure water.

asked Aug 6, 2014 by sreemathi.v

1 answer

A 5% solution (wt/volume) of cane sugar is isotonic with 0.877% (wt/volume) of urea solution.Find the molecular weight of urea,if molecular weight of sugar is 342.

asked Aug 6, 2014 by sreemathi.v

1 answer

The Henry's law constant for oxygen dissolved in water is $4.34\times 10^4$ atm at $25^{\large\circ}$C.If the partial pressure of oxygen in air is 0.2atm,under atmospheric conditions,calculate the concentration (in moles per litre) of dissolve oxygen in water in equilibrium with air at $25^{\large\circ}$C.

asked Aug 6, 2014 by sreemathi.v

1 answer

The solubility of oxygen in water is $2.43\times 10^{-3}$ mole/litre at $25^{\large\circ}$C and 1.0atm pressure.Calculate the concentration of oxygen at $25^{\large\circ}$C and 0.2atm pressure.

asked Aug 6, 2014 by sreemathi.v

1 answer

Calculate the molarity of water if its density is $1000g/m^3$

asked Aug 6, 2014 by sreemathi.v

1 answer

A sample of sulphuric acid is 98% $H_2SO_4$ by weight (density =$1.10gmL^{-1})$.Calculate normality

asked Aug 6, 2014 by sreemathi.v

1 answer

A sample of sulphuric acid is 98% $H_2SO_4$ by weight (density =$1.10gmL^{-1})$.Calculate Molarity

asked Aug 6, 2014 by sreemathi.v

1 answer

1.8g of glucose (molar mass =180) are dissolved in 60g of water.Calculate the mole fraction of glucose and water

asked Aug 6, 2014 by sreemathi.v

1 answer

1.8g of glucose (molar mass =180) are dissolved in 60g of water.Calculate the molality

asked Aug 6, 2014 by sreemathi.v

1 answer

1.23g of sodium hydroxide (molar mass =40) are dissolved in water and the solution is made to $100cm^3$.Calculate the molarity of solution.

asked Aug 6, 2014 by sreemathi.v

1 answer

Determine the osmotic pressure of a solution prepared by dissolving 25 mg of $K_2SO_4$ in 2 litre of water at 25$^{\large\circ}$ C, assuming that it is completely dissociated.

asked Aug 6, 2014 by sreemathi.v

1 answer

Determine the amount of $CaCl_2$ (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27$^{\large\circ}$ C.

asked Aug 6, 2014 by sreemathi.v

1 answer

The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 K if the Henry’s law constants for oxygen and nitrogen at 298 K are $3.30 \times 10^7$ mm and $6.51 \times 10^7$ mm respectively, calculate the composition of these gases in water.

asked Aug 6, 2014 by sreemathi.v

1 answer

Benzene and toluene form ideal solution over the entire range of composition. The vapour pressure of pure benzene and toluene at 300 K are 50.71 mm Hg and 32.06 mm Hg respectively. Calculate the mole fraction of benzene in vapour phase if 80 g of benzene is mixed with 100 g of toluene.

asked Aug 6, 2014 by sreemathi.v

1 answer

Vapour pressures of pure acetone and chloroform at 328 K are 741.8 mm Hg and 632.8 mm Hg respectively. Assuming that they form ideal solution over the entire range of composition, plot $p_{total}, p_{chloroform}$, and $p_{acetone}$ as a function of $x_{acetone}$. The experimental data observed for different compositions of mixture is:

asked Aug 6, 2014 by sreemathi.v

1 answer

100 g of liquid A (molar mass $140 g mol^{–1}$) was dissolved in 1000 g of liquid B (molar mass $180 g mol^{–1}$). The vapour pressure of pure liquid B was found to be 500 torr. Calculate the vapour pressure of pure liquid A and its vapour pressure in the solution if the total vapour pressure of the solution is 475 torr.

asked Aug 6, 2014 by sreemathi.v

1 answer