Advertisements
Advertisements
Question
The substance ‘X’, when dissolved in solvent water gave molar mass corresponding to the molecular formula ‘X3’. The van’t Hoff factor (i) is _______.
(A) 3
(B) 0.33
(C) 1.3
(D) 1
Advertisements
Solution
(B) 0.33
van’t Hoff factor (i) = Theoreticalmolecular mass/Observed molecular mass
= 1/3
= 0.33
APPEARS IN
RELATED QUESTIONS
Derive van’t Hoff general solution equation.
Define van’t Hoff factor.
3.9 g of benzoic acid dissolved in 49 g of benzene shows a depression in freezing point of 1.62 K. Calculate the van't Hoff factor and predict the nature of solute (associated or dissociated).
(Given : Molar mass of benzoic acid = 122 g mol−1, Kf for benzene = 4.9 K kg mol−1)
19.5 g of CH2FCOOH is dissolved in 500 g of water. The depression in the freezing point of water observed is 1.0°C. Calculate the van’t Hoff factor and dissociation constant of fluoroacetic acid.
Define the term abnormal molar mass.
How van’t Hoff factor is related to the degree of dissociation?
How will you convert the following in not more than two steps:
Benzoic acid to Benzaldehyde
How will you convert the following in not more than two steps:
Acetophenone to Benzoic acid
Give reasons for the following
Elevation of the boiling point of 1 M KCl solution is nearly double than that of 1 M sugar solution.
Predict whether van’t Hoff factor, (i) is less than one or greater than one in the following:
CH3COOH dissolved in water
The Van't Hoff factor (i) for a dilute aqueous solution of the strong elecrolyte barium hydroxide is (NEET) ______.
The freezing point depression constant for water is 1.86° K Kg mol-1. If 5 g Na2SO4 is dissolved in 45 g water, the depression in freezing point is 3.64°C. The Vant Hoff factor for Na2SO4 is ______.
Phenol dimerizes in benzene having van’t Hoff factor 0.54. What is the degree of association?
The van’t Hoff factor (i) accounts for ____________.
Van’t Hoff factor i is given by the expression:
(i) i = `"Normal molar mass"/"Abnormal molar mass"`
(ii) i = `"Abnormal molar mass"/"Normal molar mass"`
(iii) i = `"Observed colligative property"/"Calculated colligative property"`
(iv) i = `"Calculated colligative property"/"Observed colligative property"`
Van't Hoff factor I is given by expression.
Maximum lowering of vapour pressure is observed in the case of ______.
Geraniol, a volatile organic compound, is a component of rose oil. The density of the vapour is 0.46 g L–1 at 257°C and 100 mm Hg. The molar mass of geraniol is ______ g mol–1. (Nearest Integer)
[Given: R = 0.082 L atm K–1 mol–1]
A storage battery contains a solution of H2SO4 38% by weight. At this concentration, Van't Hoff Factor is 2.50. At the battery content freeze temperature will be ______ K.
(Kf = 1.86 K Kg mol−1)
The degree of dissociation of Ca(NO3)2 in a dilute aqueous solution containing 7 g of the salt per 100 g of water at 100°C is 70%. If the vapour pressure of water at 100°C is 760 mm. The vapour pressure of the solution is ______ mm.
Consider the reaction
\[\begin{bmatrix}\begin{array}{cc}
\phantom{.......}\ce{CH3}\\
\phantom{....}|\\
\ce{CH3CH2CH2 - \overset{⊕}{N} - CH2CH3}\\
\phantom{....}|\\
\phantom{.......}\ce{CH3}
\end{array}\end{bmatrix}\]\[\ce{OH^- ->[Heat] ?}\]
Which of the following is formed in a major amount?
A molecule M associates in a given solvent according to the equation \[\ce{M <=> (M)_n}\]. For a certain concentration of M, the van't Hoff factor was found to be 0.9 and the fraction of associated molecules was 0.2. The value of n is ______.
When 19.5 g of F – CH2 – COOH (Molar mass = 78 g mol−1), is dissolved in 500 g of water, the depression in freezing point is observed to be 1°C. Calculate the degree of dissociation of F – CH2 – COOH.
[Given: Kf for water = 1.86 K kg mol−1]
Why is the value of van't Hoff factor for ethanoic acid in benzene close to 0.5?
Why is boiling point of 1 M NaCl solution more than that of 1 M glucose solution?
