The vapour pressure of 100g water reduces from 3000 Nm-2 to 2985 Nm-2 when 5g of substance 'X' is dissolved in it. Substance 'X' is
180 is the molecular weight of glucose (C6H12O6), thus the substance X is glucose.
White P reacts with caustic soda, the products are PH3 and NaH2PO2. This reaction is an example of
The above reaction is an example of disproportionation reaction, i.e. the reaction in which oxidation and reduction take place simultaneously.
If a be the edge length of the unit cell and r be the radius of an atom then for fee arrangement, the correct relation is
4a = r
4r = a
4r = a
4r = a
Given, the edge length of the unit cell = a and, radius of the sphere = r
AC2 = AB2 + AC2
= a2 + a2
Therefore, AC = a
But, in figure, AC = 4r
Therefore, 4r = a
How long it will take to deposit 1.0 g of chromium when a current of 1.25 A flows through a solution of chromium (III) sulphate ? (Molar mass of Cr = 52)
None of these
Cr3+ + 3e- Cr(s)
3 mol or 3 x 96500 C of electricity are needed to deposit 1 mol or 52 g of Cr
52 gm of Cr will require current = 3 x 96500C
1 gm of Cr will require current = = 5567.3C
Now, number of coulombs = current (ampere) x t (seconds)
The complex ion which has no d-electrons in the central metal atom is
In [MnO4]-, the oxidation state of Mn is + 7
Mn(25) = [Ar] 3d54s2
Mn7+ = [Ar]
Thus, in [MnO4]- no d-electron is present.
A solid AB has the NaCl structure. If radius of cation A+ is 120 pm, the maximum possible value of the radius of the anion B- is
For NaCl crystal,
Radius of cation/ radius of anion = 0.414
For a reaction, A+ B Product, the rate is given by,
r = k[A]1/2[B]2
What is the order of the reaction?
Order of a reaction is the sum of the power to which the concentration terms are raised in the rate law equation to express the observed rate of the reaction
Hence, order =
Dihedral angle between two methyl groups of n-butane in the gauche and anti forms are
The angle between C-C and C-H bonds on adjacent carbon atoms in any conformation is called dihedral angle. Hence, the dihedral angle in case of gauche is 60°and in anti form is 180°.
The solubility of saturated solution of Ag2CrO4 is s mol L-1. What is its solubility product?
Ag2CrO4 2Ag+ + Cr
s mol/L 2s mol/L s mol/L
Hence, the solubility product is
Ksp of Ag2CrO4 = [Ag+]2[Cr]
Therefore, 4s3 is the solubility product.
The number of phase in a colloidal system is
Colloidal solution is of heterogeneous nature. It consists oftwo phases ie, a dispersed phase and a dispersion medium.