Chemistry

Q.

Calculate(a)molality (b)molarity and (c)mole fraction of KI if the density of 20% (mass/mass) aqueous KI is1.202 g mL^-1.

Q. Calculate the mass of Urea required in making 2.5 kg of 0.25 molal aqueous solution.

Q.

Henrys law constant for $C{O}_2$ in water is $1.6\times {10}^8$ Pa at 298K.

Calculate quantity of $C{O}_2$ in 500 mL of soda water when packed under 2.5 atm $C{O}_2$ pressure at 298K.

Q.

QUESTION 2.5

A solution of glucose in water is labelled as $10\%w/w$. What should be the molality and mole fraction of each component in the solution? If the density of solution is $1.2gm{L}^{-1}$, then what shall be the molarity of the solution?

Q.

Calculate the mole fraction of benzene in a solution containing 30% by mass of carbon tetrachloride

Q.

QUESTION 2.4

Concentrated nitric acid used in laboratory work is $68\%$ nitric acid by aqueous solution. What should be the molarity of such a sample of the acid if the density of the solution is 1.504 g mL−1mL^{-1}mL−1 ?

Q. $H_{2}S$ , a toxic gas with a rotten egg like smell is used for the qualitative analysis. If the solubility of $H_{2}S$ in the water at STP is $0.195m$, then Henry's law constant (in atm) is nearly :

1. 28.94
2. 285
3. 145.2
4. 2890.4

Q. Calculate the molarity of a solution containing $5g\text{of}NaOH\text{in}450mL$ solution.

Q.

The density of 3M solution of NaCl is 1.25 g/mL. Calculate molality of the solution.

Q.

The vapour pressure of pure liquids A and B are 450 and 700 mm Hg respectively, at 350 K. Find out the composition of the liquid mixture if total vapour pressure is 600 mm Hg. Also find the composition of the vapour phase.

Q.

State henrys law and its applications.

Q.

Explain how to calculate the number of atoms of a certain element in a given mass of a compound.

Q.

Calculate molar mass of CO(NO3)2.6H2O

Q.

$H_{2}S$ is a toxic gas with rotten egg like smell , is used for the qualitative analysis . If the solubility of $H_{2}S$ in water at STP is 0.195M , calculate Henry's law constant .

Q.

Define bond order. Calculate the bond order of C₂, H₂, and N₂.

Q.

A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing point of pure water is 273.15 K.

Q.

in a crystalline solid, anions B are arranged in a cubic close packing. cations are equally distributed between octahedral and tetrahedral voids. if all the octahedral voids are occupied, what is the formula of the solid

Q. Calculate the molecular mass of glucose $\left(C_6{H}_{12}{O}_6\right)$ molecule.

Q.

What is meant by exothermic and endothermic reactions? Give examples.

Q.

Define Anti Markovnikovs Rule And Markovnikovs with example.

Q.

Calculate the mass of a non-volatile solute (molar mass 40 g mol⁻¹) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.

Q.

On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper oxide (black) oxygen gas and a brown gas $\mathrm{X}$ is formed.

(a) Write a balanced chemical equation of the reaction

(b) Identify the brown gas $\mathrm{X}$ evolved

(c) Identify the type of reaction

(d) What could be the pH range of the aqueous solution of the gas $\mathrm{X}$?

Q.

Calculate the molarity of each of the following solutions: (a) 30 g of Co(NO₃)₂. 6H₂O in 4.3 L of solution (b) 30 mL of 0.5 M H₂SO₄ diluted to 500 mL.

Q.

QUESTION 2.7

A solution is obtained by mixing 300 g of $25\%$ solution and 400 g of $40\%$ solution by mass. Calculate the mass percentage of the resulting solution.

Q.

What is collision frequency?

Q.

What are the first $30$ elements?

Q. Which one of the following has maximum number of atoms?

1. $1g\text{of}Ag\left(s\right)$
   $\text{Atomic mass of Ag=108}$
2. $1g\text{of}{O}_2\left(g\right)$
   $\text{Atomic mass of O=16}$
3. $1g\text{of}Li\left(s\right)$
   $\text{Atomic mass of Li=7}$
4. $1g\text{of}Mg\left(s\right)$
   $\text{Atomic mass of Mg=24}$

Q.

The boiling point of benzene is 353.23 K. When 1.80 g of a non-volatile solute was dissolved in 90 g benzene, the boiling point is raised to 354.11 K. Calculate the molar mass of the solute. $\left(K_{b}forbenzeneis2.53Kkgmo{l}^{-1}\right)$

1. $58.0gmo{l}^{-1}$

2. $68.0gmo{l}^{-1}$

3. $78.0gmo{l}^{-1}$

4. $48.0gmo{l}^{-1}$

Q.

The partial pressure of ethane over a solution containing 6.56 × 10⁻³ g of ethane is 1 bar. If the solution contains 5.00 × 10⁻² g of ethane, then what shall be the partial pressure of the gas?

Q.

A solution containing 30 g of non-volatile solute exactly in 90 g of water has a

vapour pressure of 2.8 kPa at 298 K. Further, 18 g of water is then added to

the solution and the new vapour pressure becomes 2.9 kPa at 298 K. Calculate:

1. molar mass of the solute

2. vapour pressure of water at 298 K.