Molality

Q. 32. 80 g of h2 is reacted with 80 g of o2 to form water. find out the mass of water obtained.which substance is the limiting reagent.

Q.

10 mole of ideal gas expand isothermally and reversibly from a pressure of 10 atm to 1 atm at 300 K. What is the largest mass which can lifted through a height of 100 meter?

1. 31842 kg

2. 58.55 kg

3. 342.58 kg

4. None of these

Q. 18. 20%of N2O4 molecules are dissociated into NO2 in a sample of gas at 300k and 760 Torr. Calculate the density of the equilibrium mixture 1)ABO2 2)A2BO2 3)A2B3O4 4)AB2O2

Q. a given solution of hydrogen peroxide is 30 volume. its conc in terms of molarity is a. 9.1 M b. 2.68 M c. 2.5 M d. 26.8M

Q. If the density of methanol is 0.793kg/l, what is its volume needed for making 2.5l of its 0.25M solution ?

Q. Find the molarity and molality of a 15% (w/w) $H_{2}S{O}_4$ solution.
(Density of the solution is 1.10 g/mL)

1. 1.53 M, 1.64 m
2. 1.68 M, 1.68 m
3. 1.80 M 1.68 m
4. 1.68 M 1.80 m

Q. when 2.94 moles of Iodine and 8.1 mole of hydrogen are heated at a constant volume at 722 K until the equilbrium is achieved, 5.64 moles of HI are formed find the equilbrium constant

Q.

1 molal solution is one that contains one mole of solute in:

1. 1000g of solvent

2. 1L of solvent

3. 1L of solution

4. 22.4L of solution

Q. 26. Sodium carbonate contains 43.4% Na, 11.3% Cand 45.3% O. If the law of constant composition isvalid then weight of Na in 6 g of Na, COa obtainedfrom other source will be3(2) 3.5 g(1) 1.4 g(4) 1.8 g) 2.6 g

Q. Calculate the volume of HNO_3 ( sp. gravity 1.05 gm/ml containing 12.6 w/W of HNO_3 ) that reduce into NO is required to oxidise iron 1 g FeSO_4.7H_2O in acid medium. (a)70ml (b)0.57ml (c)80ml (d)0.65ml

Q. Calculate the molality of a 1 L solution of 93% $H_{2}S{O}_4$ (w/v). The density of the solution is 1.84 g/mol.

1. 10.4 m
2. 5.1 m
3. 12.7 m
4. 9.3 m

Q. The density of a 6 M solution of sodium chloride is 1.525 g/mL. Calculate the molality of the solution.

1. 1.18 m
2. 2.42 m
3. 5.11 m
4. 3.79 m

Q. In which of the following formula mass is preffered over molecular mass? Water Sodium chloride Methane Ammonia

Q. If the concentration of a sodium hydroxide aqueous solution is 50% by mass, calculate the molality of the solution.

1. 25.0 m
2. 0.5 m
3. 12.5 m
4. 13.8 m

Q. If the density of methanol is 0.793 Kg L^-1, what is its volume needed for making 2.5 L of its 0.25 M solution.

Q.

18 g of glucose (C₆H₁₂O₆) is present in 1000 g of an aqueous solution of glucose. The molality of this solution is:

1. 1.1m

2. 0.5m

3. 1m

4. 0.1m

Q. A solution of NaOH is prepared by dissolving 4g of NaOH in 500ml of solution. Calculate molarity of the solution

Q. What is the vapour pressure of a solution at ${100}^{\circ }C$ containing 18 g of water and 1.71 g of sucrose (non-volatile)? $\text{Given: Molecular formula of sucrose is}{C}_{12}{H}_{22}{O}_{11}$
At ${100}^{\circ }C$, vapour pressure of pure water is $1atm$.

1. $415.3torr$
2. $450.5torr$
3. $756.2torr$
4. $788.4torr$

Q. In an electrolysis experiment, a current was passed for 5 hours through two cells connected in series. The first cell contains a solution of gold salt and the second cell contains copper sulphate solution. $9.85g$ of gold was deposited in the first cell. If the oxidation number of gold is +3, find the amount of copper deposited on the cathode in the second cell and the magnitude of the current in ampere respectively.
Given:
$\text{Molar mass of gold}=197g/mol$
$\text{Molar mass of copper}=63.5g/mol$

1. $70.5g\text{and}0.35A$
2. $4.67g\text{and}0.804A$
3. $70.5g\text{and}0.26A$
4. $2.65g\text{and}2A$

Q. Silicon dioxide made up of silicon and oxygen contains 46.7% by mass of silicon. With what mass of oxygen will 10g of silicon combine

Q. The molality of a sulphuric acid solution is 0.2 mol/kg. Calculate the total weight of the solution having 1000 g, of solvent:-

1. 1000 g
2. 1098.6 g
3. 980.4 g
4. 1019.6 g

Q. "PCl5(g) PCl3(g) + Cl2(g) Vapour density is found to be 100 when 1 mole of PCl5 is taken in a 10 litre flask at 27* C." How did the initial density equals to M/2? Since volume is 10 L shouldnt ot be M/10?

Q. During the experiment you are given 2.5 m acetone solution in heptane (molar mass = 100 g/mol) having a density of 0.5 g/mL. Find the mole fraction of solute.

1. 0.3
2. 0.2
3. 0.85
4. 0.02

Q.

Calculate Molality (in $M$) of a solution in which 36 gm glucose is dissolved in 500 gm water.

1. 0.8

2. 0.4

3. 0.2

4. 0.36

Q. a given solution of hydrogen peroxide is 30 volume. its conc in terms of molarity is a. 9.1 M b. 2.68 M c. 2.5 M d. 26.8M

Q. Carbon tetrachloride $\left(CC{l}_4\right)$ is mixed in $390\text{g}$ of benzene to make a solution for supporting an organic chemical reaction in which mole fraction of benzene is $0.91$. Find the molality of the $CC{l}_4$ solution.

1. $2.67\text{m}$
2. $4.25\text{m}$
3. $1.26\text{m}$
4. $4.44\text{m}$

Q. 1.84 g mixture of CaCO_3 and MgCO_3 was heated to cons†an t weight till 0.96 g residue formed. %(by mass) of MgCO_3 in sample was

Q. Calculate the molality of a 20% $CaC{O}_3$ solution (by mass). The density of the solution is 1.2 g/mL.

1. 1.25 m
2. 2.50 m
3. 2.08 m
4. 1.52 m

Q. Number of mole of NaOH in 27cm^3 of 0.15 M NaOH solution is

Q. If the concentration of glucose in blood is 0.9g/L , what will be the molarity of glucose in blood