A cell, with cell constant 0.4 cm-1, has the resistance of 40 ohm of a 0.01 M solution of an electrolyte, then the molar conductivity in ohm-1 cm2 mol-1 will be
104
103
102
1
If the standard elelctrode potential for the cell Zn | Zn2+ (aq) || Cu2+ (aq) | Cu is 1.10 V, then the maximum work done by this cell will be
-106.15 kJ
-212.30 kJ
-318.45 kJ
-424.60 kJ
2A → B + C
It would be a zero order reaction when
the rate of reaction is proportional to square of concentration of A
the rate of reaction remains same at any concentration of A
the rate remains unchanged at any concentration of B and C
the rate of reaction doubles if concentration of B is increased to double
The reaction A → B follows first order kinetics. The time taken for 0.8 mole of A to produce 0.6 mole of B is 1 h. What is the time taken for conversion of 0.9 mole of A to produce 0.675 mole of B?
1 h
0.5 h
0.25 h
2 h
The structure of ionic compound with Schottky defects has
same number of cationic and anionic vacancies
anionic vacancy and interstitial anion
cationic vacancies
cationic vacancies and interstitial cation
If a pentavalent impurity is mixed in the crystal-lattice of germanium then the semiconductor formed will be
p-type semiconductor
n-type semiconductor
(a) and (b) both
None of the above
B.
n-type semiconductor
Pentavalent elements have one excess valence electron after forming the four covalent bond normally formed by germanium. The excess electrons give rise to electrical conductance. It is called n-type semi-conductors, the symbol 'n' indicates that the negative charge flows in them.
A compound formed by elements X and Y crystallises in a cubic structure in which the X atoms are at the comers of a cube and the Y atoms are at the face centres. The formula of the compound is
XY3
X3Y
XY
XY2