For preparing 3.00 L of 1M NaOH by mixing portions of two stock solutions (A and B) of 2.50 M NaOH and 0.40 M NaOH respectively. Find out the amount of B stock solution (in L) added.
8.57 L
2.14 L
1.28 L
7.51 L
The Vividh Bharti Station of All India Radio, Delhi, broadcasts on a frequency of 1,368 kHz (Kilohertz). Calculate the wavelength () of the electromagnetic radiation emitted by transmitter. Which part of the electromagnetic spectrum does it belong to?
319.4 m and X-rays
319.4 m and radiowave
219.3 m and microwave
219.3 m and radiowave
In an atom, an electron is moving with a speed of 600 m/s with an accuracy of 0.005%. Certainty with which the position of the electron can be located is
(Given, h= 6.6 x 10-34 kg m2 s-1, mass of electron em = 9.1 x 10-31 kg)
215 x 10-3 m
2.78 x 10-3 m
1.92 x 10-3 m
3.24 x 10-3 m
What would be the heat released when an aqueous solution containing 0.5 mole of HNO3 is mixed with 0.3 mole of OH-? (enthalpy of neutralisation is- 57.1 kJ)
28.5 kJ
17.1 kJ
45.7 kJ
1.7 kJ
The number average molar mass and mass average molar mass of a polymer are respectively 30,000 and 40,000. The
polydispersity index (PDI) of the polymer is
-1
0
> 1
< 1
The charge/size ratio of a cation determines its polarising power. Which one of the following sequences represents the increasing order of the polarising power of the cationic species, K+, Ca2+, Mg2+, Be2+?
K+ < Ca2+ < Mg2+ < Be2+
Be2+ < K2+ < Ca2+ < Mg2+
Mg2+< Be2+ < K+ < Ca2+
Ca2+ < Mg2+ < Be+ < K+
A.
K+ < Ca2+ < Mg2+ < Be2+
High charge and small size of the cations increases polarisation. As the size of the given cations decreases as
K+ > Ca2+ > Mg2+ > Be2+
Thus, polarising power increases as
K+ < Ca2+ < Mg2+ < Be2+
In an amino acid, the carboxyl group ionises at pKa = 2.34 and ammonium ion at pKa2 = 9.60. The isoelectric point of the amino acid is at pH
4.32
3.34
9.46
5.97
0.40 g of helium in a bulb at a temperature of T K had a pressure of p atm. When the bulb was immersed in water bath at temperature 50 K more than the first one, 0.08 g of gas had to be removed to restore the original pressure. T is
500 K
400 K
600 K
200 K
What percentage of -D-(+-glucopyranose is found at equilibrium in the aqueous solution?
64%
36%
100%
50%
Which of the following is correctly arranged in order of increasing weight?
0.0105 equivalent of H2CO2 ·2H2O < 0.625 g of Fe < 0.006 g atom of Ag <6.0 x 1021 atoms of Zn
0.625 g of Fe < 0.0105 equivalent of H2C2O4 ·2H2O < 6.0 x 1021 atoms of Zn < 0.006 g atom of Ag
0.625 g of Fe < 6.0 x 1021 atoms of Zn < 0.006 g atom of Ag < 0.0105 equivalent of H2C2O4 ·2H2O
0.0105 equivalent of H2C2O4. 2H2O < 0.006 g atom of Ag <6.0 x 1021 atoms of Zn < 0.625 g of Fe