Advertisements
Advertisements
Question
Calculate the amount of benzoic acid (C6H5COOH) required for preparing 250 mL of 0.15 M solution in methanol.
Advertisements
Solution
V = 250 mL, m = 0.15 M, Molecular weight of solute = 122, Amount of solute = ?
m = `"Weight of solute"/"Molecular weight of solute" xx 1000/"Volume of solution in mL"`
or 0.15 = `w/122 xx 1000/250`
w = `(0.15 xx 122 xx 250)/1000`
= 4.575 g
RELATED QUESTIONS
Derive van’t Hoff general solution equation.
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
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.
How will you convert the following in not more than two steps:
Benzoic acid to Benzaldehyde
Predict whether van’t Hoff factor, (i) is less than one or greater than one in the following:
CH3COOH dissolved in water
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 ______.
The van’t Hoff factor (i) accounts for ____________.
We have three aqueous solutions of NaCl labelled as ‘A’, ‘B’ and ‘C’ with concentrations 0.1 M, 0.01 M and 0.001 M, respectively. The value of van’t Hoff factor for these solutions will be in the order ______.
Van't Hoff factor I is given by expression.
What is the expected each water van't Hoff factor for and K4[F4(CN6)] when it completely dissociated in waters.
Maximum lowering of vapour pressure is observed in the case of ______.
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 ______.
Why is boiling point of 1 M NaCl solution more than that of 1 M glucose solution?
