=> Ans. Cell constant of a conductivity cell is defined as the ratio of the distance between the electrodes divided by the area of cross section of the electrodes.
2➤ What is specific conductance or conductivity?
=> Ans. The reciprocal of specific resistance or resistivity is called specific conductance or conductivity.
3➤ It in the conductance of a conductor that is 1 m in length and 1 m² in cross section area in SI units Q. 34. A conductivity cell has two electrodes 20 mm apart and of cross section area 18 cm. Find the cell constant.
=> Given: Distance between two electrodes -/-20 mm Cross section area-a-18 cm² Cell constant-b-? Coll constant-1.111 em
4➤ What is voltaic or galvanic cell?
=> Ans. Voltale or galvanie cell: An electrochemical cell in which a spontaneous chemical reaction occurs producing electricity and where a chemical energy is converted into an electrical energy is called voltaic cell or galvanic cell. B.g. Daniell cell, dry cell, lead storage battery, fuel cells, etc.
5➤ What is the significance of (0) the single vertical line and (i) double vertical lines in the formulation galvanic cell?
=> Consider representation of Daniell cell, 22¹ IMC² MC Single vertical line repensents separation of two phases, solid Zn, and solution of ions (1) Double vertical lines represent a salt beldge.
6➤ What is standard reduction potential"
=> Ans. Standard reduction potential: It is defined as the difference of electrical potential between metal electrode and the solution around it at equilibrium due to reduction reaction, when all the substances involved in the reduction reaction are in their standard states of unit activity or concentration at constant temperature (25 °C)
7➤ Identify the strongest and the weakest agents from the electrochemical series. oxidizing
=> Ans. From the electrochemical series, (a) The strongest oxidising agent is fluorine since it has the highest standard reduction potential (+287 V) (b) The weakest oxidising agent (or the strongest reducing agent) is lithium since it has the lowest standard reduction potential, (-3.045 V).
8➤ Give SI unit of resistivity
=> Ans: The SI unit of resistivity is 52 m.
9➤ What is cell voltage?
=> Ans: The difference in the electrical potential between anode and cathode is called cell voltage.
10➤ Write a mathematical expression for Standard Cell Potential.
=> The standard cell potential can be written as: El Ed (cathode) - Ed (anode) Omitting the subscript 'red', we have EE (cathode)- E" (anode).
11➤ Name the process by which water produces hydrogen gas at cathode during electrolysis of aqueous NaCl.
=> Ans: Reduction of water to hydrogen gas
12➤ Give the chemical composition present in the salt bridge.
=> Ans: Saturated solution of the KCI or NH4NO, and 5 % agar solution
13➤ Write the potential produced through the NICAD storage cell.
=> Ans: NICAD produces a potential of about 1.4 V.
14➤ Write an equation that shows the relationship between molar conductivity and degree of dissociation of weak electrolyte.
=> Ans: The relationship between molar conductivity () and degree of dissociation (a) of weak electrolyte is given as a=*/* where, ** Limiting molar conductivity
