C is not a property of metals
Explanation:
a) Anode:
Cathode :
b)
c) As , the reaction is spontaneous.
d)
Explanation:
a) Here Ni undergoes oxidation by loss of electrons, thus act as anode. Hydrogen undergoes reduction by gain of electrons and thus act as cathode.
Anode:
Cathode :
b) The representation is given by writing the anode on left hand side followed by its ion with its molar concentration. It is followed by a slat bridge. Then the cathodic ion with its molar concentration is written and then the cathode.
c)
Where both are standard reduction potentials.
= +ve, reaction is spontaneous
= -ve, reaction is non spontaneous
= 0, reaction is in equilibrium
Thus as , the reaction is spontaneous.
d) The standard emf of a cell is related to Gibbs free energy by following relation:
= standard gibbs free energy
n= no of electrons gained or lost
F= faraday's constant
= standard emf
Thus value of Gibbs free energy is -48250 Joules.
Answer:
Molality = 0.43 m
Explanation:
Given data:
Mass of barium sulfide = 25.4 g
Mass of water = 349 g (349 g/1000 = 0.349 Kg)
Molality of water = ?
Solution:
Number of moles of barium sulfide:
Number of moles = mass/molar mass
Number of moles = 25.4 g/169.39 g/mol
Number of moles = 0.15 mol
Molality:
Molality = number of moles o f solute/ Kg of solvent
Molality = 0.15 mol / 0.349 Kg
Molality = 0.43 m
The boiling point of oxygen is higher than nitrogen's boiling
The reason the boiling point of O2 is higher is not because of increased van der Waals interactions, but simple physics. The mass of a molecule of O2 is greater than that of a molecule of N2, so the molecule of O2 traveling at a speed sufficient to break out of the liquid phase has a greater kinetic energy than an analogous N2 molecule.
The net effect is that more energy must be distributed throughout a sample of O2 to achieve a given vapor pressure (in this case equal to atmospheric pressure) than for a sample of N2. More energy means greater temperature.
