Advertisements
Advertisements
Question
22.22 gram of urea was dissolved in 300 grams of water. Calculate the number of moles of urea and molality of the urea solution.
(Given: Molar mass of urea = 60 gram mol−1)
Advertisements
Solution
Given: Molar mass of urea = 60 gram mol−1
Moles of urea = `22.22/60`
= 0.370 moles
Formula: Molality (m) = `"Moles of urea"/"Mass of water" xx 1000`
= `(0.370 xx 1000)/300`
= 1.23 moles kg−1
APPEARS IN
RELATED QUESTIONS
Calculate the mole fraction of benzene in solution containing 30% by mass in carbon tetrachloride.
Calculate (a) molality (b) molarity and (c) mole fraction of KI if the density of 20% (mass/mass) aqueous KI is 1.202 g mL−1.
A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? If the density of solution is 1.2 g mL−1, then what shall be the molarity of the solution?
If the density of some lake water is 1.25 g mL−1 and contains 92 g of Na+ ions per kg of water, calculate the molality of Na+ ions in the lake.
Nalorphene (C19H21NO3), similar to morphine, is used to combat withdrawal symptoms in narcotic users. Dose of nalorphene generally given is 1.5 mg. Calculate the mass of 1.5 × 10−3 m aqueous solution required for the above dose.
When KOH solution is added to potassium dichromate solution the colour of solution
changes to yellow, because _______
(A) chromate ion changes to dichromate ion
(B) dichromate ion changes to chromate ion
(C) oxidation number of chromium changes from + 6 to + 4
(D) oxidation number of chromium changes from + 4 to +6
Define Normality.
A sample of 12 M Concentrated hydrochloric acid has a density 1.2 M gL-1 calculate the molality.
1 M, 2.5 litre NaOH solution is mixed with another 0.5 M, 3 litre NaOH solution. Then find out the molarity of the resultant solution:
4.0 g of NaOH is dissolved in 100 ml solution. The normality of the solution is ____________.
An aqueous solution of glucose is 10% in strength. The volume in which 1 g mole of it is dissolved, will be:
2.5 litres of NaCl solution contain 5 moles of the solute. What is the molarity?
5 ml of N HCl, 20 ml of N/2 H2SO4 and 30 ml of N/3 HNO3 are mixed together and volume made to one litre. The normality of the resulting solution is:
For preparing 0.1 N solution of a compound from its impure sample of which the percentage purity is known, the weight of the substance required will be:
If N/10 50 ml H2SO4, N/3 30 ml HNO3, N/2 10 ml HCl is mixed and solution is made to 1 L. Then normality of the resultant solution is:
A solution made by dissolving 40 g NaOH in 1000 g of water is ____________.
A solution is prepared by dissolving 10 g NaOH in 1250 mL of a solvent of density 0.8 mL/g. The molality of the solution in mol kg–1 is:
Mole fraction of C3H5(OH)3 in a solution of 36 g of water and 46 g of glycerine is ______.
Cone. H2SO4 is 98% H2SO4 by mass has d = 1.84 g cm−3. Volume of acid required to make one litre of 0.1 M H2SO4 is:
Which of the following is a correct statement for C2H5Br?
Given below are two statements labelled as Assertion (A) and Reason (R).
Assertion (A): Molarity of a solution changes with temperature.
Reason (R): Molarity is a colligative property.
Select the most appropriate answer from the options given below:
Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why?
(iii) w/V (mass by volume percentage)
Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why?
x (mole fraction)
The number of electrons involved in the reduction of one nitrate ion to hydrazine is
What is molarity of resulting solution obtained by mixing 8.5 L of 0.5 m urea solution and 500 ml of 2 m urea solution?
3.36 M sulphuric acid solution is 29% H2SO4 calculate the density of the solution.
A given solution of H2O2 is 30 volumes. Its concentration in terms of molarity is ______.
