Advertisements
Advertisements
प्रश्न
Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why?
m (Molality)
Advertisements
उत्तर
The no. of moles of solute per kg of solvent
Molality (m) = `"Moles of solute"/"Mass of solvent in kg"`
Effect of temperature: Mass % ppm, mole fraction and molality do not change with temperature where as molarity, volume percentage and mass by volume percentage changes with temperature because volume of solution (liquid) varies with changes in temperature.
APPEARS IN
संबंधित प्रश्न
Why is molality of a solution independent of temperature?
Calculate the mass of urea (NH2CONH2) required in making 2.5 kg of 0.25 molal aqueous solution.
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.
Define mass percentage.
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?
How many mL of 0.1 M HCl are required to react completely with 1 g mixture of Na2CO3 and NaHCO3 containing equimolar amounts of both?
An antifreeze solution is prepared from 222.6 g of ethylene glycol (C2H6O2) and 200 g of water. Calculate the molality of the solution. If the density of the solution is 1.072 g mL−1, then what shall be the molarity of the solution?
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
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)
Define Normality.
Molarity of the solution is ____________.
An X molal solution of a compound in benzene has mole fraction of solute equal to 0.2. The value of X is ____________.
4.0 g of NaOH is dissolved in 100 ml solution. The normality of the solution is ____________.
10 g of NaCl is dissolved in 106 g of the solution. Its concentration is ____________.
The volume of 4 N HCl and 10 N HCl required to make 1 litre of 6 N HCl are ____________.
Which of the following concentration terms is/are independent of temperature?
Match the terms given in Column I with expressions given in Column II.
| Column I | Column II |
| (i) Mass percentage | (a) `"Number of moles of the solute component"/"Volume of solution in litres"` |
| (ii) Volume percentage | (b) `"Number of moles of a component"/"Total number of moles of all the components"` |
| (iii) Mole fraction | (c) `"Volume of the solute component in solution"/"Total volume of solution" xx 100` |
| (iv) Molality | (d) `"Mass of the solute component in solution"/"Total mass of the solution" xx 100` |
| (v) Molarity | (e) `"Number of moles of the solute components"/"Mass of solvent in kilograms"` |
Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why?
w/w (mass percentage)
What is the ratio of mass of an electron to the mass of a proton?
250 mL of 0.5 M NaOH was added to 500 mL of 1 M HCl. The number of unreacted HCl molecules in the solution after complete reaction is ______ × 1021. (Nearest integer) (NA = 6.022 × 1023).
