Indo Korean Workshop

A Zinc bromine battery is charged at 20mA current until 90,000 coulombs are passed. If the battery is discharged at 20mA, how many hours it would last assuming it exhibits 100% Coulombic Efficiency

• 1250

• 625

• 900

• 1800

If 20mA is continuously passed in the Zn-Br flow battery, what is the minimum flow rate (in nano L/s) of 2 M ZnBr₂ solution that can support the current

• 50

• 100

• 150

• 200

Calculate the potential of Cl^- concentration cell given below which uses sparingly soluble salt MCl.

M(s), MCl(s) | Cl^- _{(0.01 M)} ||Cl^- _{(1 M)} | MCl(s), M(s)

• 0.118 V

• -0.118 V

• 0.059

• -0.059

• -2374

• -237.4

• -1187

• -474.6

In a fuel cell of 5cm² active area, when a current density of 100mA/cm² was flowing what is the minimum flow rate of H₂ (moles/min) required to sustain the current density?

• 9.3

A Cu/Zn cell loses 2g of Zn due to electrooxidation. Calculate the electricity used in Ah. Given molar mass of Zn is 65.38g mol^-1

• 1.64 Ah

• 4.83 Ah

• 2.93 Ah

• 3.83 Ah

Calculate value of the impedence of the following RC circuit at 100 Hz. Where R has the value 100 Ω and C is 15.9 μF

• 141 Ω

• 637 Ω

• 425 Ω

• 100

The amount of Zn packed in a Zn-air battery is 65.38g. When a current of 2A is drawn continuously, how many hours will the battery last ? Given the atomic weight of Zn is 65.38g mol^-1

• 13.4

• 26.8

• 53.6

• 107.2