14.1 -technology of cells and batteries

electric cell

a device that turns chemical energy into electrical energy. Composed of 2 electrodes and 1 electrolyte

Battery

a group of two or more electric cells connected to each other in a series, like railway cars in a train

Voltaic pile

Invented by Alessandro Volta, made by alternating zinc and copper disks separated by pieces of fabric soaked in salt water (the electrolyte).

electrodes

a device that moves electrons into or out of a solution by conduction. Cathode and Anode

Electrolyte

A substance that dissolves in water to give a solution that conducts electric current.

In a voltaic cell, the cathode is the _____________ electrode, and the anode is the ______________ electrode.

positive , negative

Electrons move from the ____________ of the battery, through the external circuit to the ____________

anode, cathode

A battery only produces electricity when.....

there is an external conducting path, such as a wire, through which electrons can move.

voltmeter

A device used to measure voltage, or the electrical potential energy difference per unit electrical charge, between any two points in an electrical circuit

electrical potential difference (voltage)

the energy difference per unit charge, measured in volts. Ratio of energy to charge. Not dependant on size of the cell.

The larger cells can ___________ more _________, BUT the ratio of energy to charge is the __________ as smaller cells.

store, energy, same

Voltage

The potential difference measured in volts. The amount of work to be done to move a charge from one point to another along an electric circuit. Mainly depends on the chemical composition of the reactants int he cell.

Electric current

measured by an ammeter in amperes (A), it is a measure of the rate of the flow of charge past a point in the electrical current.

The __________ the electrical cell of a particular type, the ________ the current that can be produced by the cell

larger, greater

Charge

is transferred by a cell or battery, and is measured in coulombs (c) and expresses the total charge transferred by the movement of charged particles