What are the components of a voltaic cell?

• The anode is an electrode where oxidation occurs.

• The cathode is an electrode where reduction occurs.

• A salt bridge is a chamber of electrolytes necessary to complete the circuit in a voltaic cell.

• The oxidation and reduction reactions are separated into compartments called half-cells.

•The external circut is used to conduct the flow of electrons between the electrodes of the voltaic cell and usually includes a load.

• The load is the part of the circuit which utilizes the flow of electrons to perform some function.

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.