One mole of P4O10 is allowed to react fully with dust and salt-free doubly distilled water and the volume is made up to 1L. What is the normality of the so-generated orthophosphoric acid?
P4O10 + 6H2O → 4H3PO4
1.0 N
8.0 N
12.0 N
4.0 N
C.
12.0 N
P4O10 + 6H2O → 4H3PO4
1mol 4mol
Thus, 4 moles of orthophosphoric acid are generated in 1L solution.
Molarity = 4M
and normality = molarity × basicity = 4 × 3 = 12.0 N
Which of the following statements about the monomer and dimer of NO2 is/are not true?
Both are diamagnetic
Both are paramagnetic
The dimer is paramagnetic and the monomer is not
all of these
Which one of the following statements regarding helium is incorrect ?
It is used to fill gas balloons instead of hydrogen because it is lighter and non-inflammable
It is used as a cryogenic agent for carrying out experiments at low temperatures
It is used to produce and sustain powerful superconducting magnets
It is used in gas cooled nuclear reactors
Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species?
Cl <F <S <CO
O <S <F <Cl
S <O <Cl <F
F <Cl <O <S
Sodium thiosulphate is used in photography
as AgBr grain is reduced to non-metallic silve
to convert metallic silver into silver salt
to remove reduced silver
to remove undecomposed AgBr in the form of Na3[Ag(S2O3)2] (a complex salt)
The decreasing order of electron affinity is
I > Br > Cl > F
Br > Cl > F > I
F > Cl > Br > I
Cl > F > Br > I
For the reaction, 2SO2 + O2(excess) → 2SO3 the order of reaction with respect to O2 is
two
three
zero
one
In the manufacture of ammonia by Haber's process, N2 (g) + 3H2(g) 2NH3(g) + 92.3kJ. which of the following conditions is unfavourable?
reducing the temperature
Removing ammonia as it is formed
Increasing the temperature
Increasing the pressure