11.1 Cells and Batteries (Page 437-444)

Homework: Page 445 # 2, 5, 8 Key Concepts (Page 445)

In a voltaic cell, chemical reaction involve two different metals or metals compounds (called electrodes), and a conducting solution or a paste (called an electrolyte).Watch This And this if you want more

• A battery is a connection of two or more cells.

A dry cell contains an electrolyte that is a paste, whereas a wet cell contains an electrolyte that is a liquid solution.

• A primary cell can be used only once, and then it is discarded, whereas a secondary cell can be recharged many times.

A fuel cell generates electricity using chemical reactions of fuel stored outside the cell.

A solar cell converts sunlight, a renewable energy source, into electrical energy.

Electric and Hybrid Vehicles:1. Compare the consequences to the environment of using an electric car and a hybrid car?

• A regular gas-burning car wastes fuel and releases carbon dioxide at all times, even when stuck in traffic.

• An electric car charged by the power generated by an oil burning generating plant converts twice as much energy to making a car move.

• It thus wastes less fuel and produces less CO2. Hybrids save on fuel by converting braking energy into electrical energy which can later be used to move the car.

• Hybrids, like electric cars, waste less fuel and produce less CO2 than regular gas cars.

3. Write a description of the different types of cells and list examples of each one.

Type of Cell Description Examples

Dry Cell A cell that contains an electrolyte that is a paste.

Zinc-carbon cellsAlkaline cells

Wet Cell A cell that contains an electrolyte that is a liquid.

Lead acid batteries

Type of Cell Description Examples

Primary Cell A cell that can be used only once.

Zinc-carbon cells

Secondary Cell A cell that can be recharged.

Nickel-metal hydride cells

Type of Cell Description Examples

Fuel Cell A cell that generates electricity through the chemical reactions of fuel that is stored outside the cell.

Hydrogen fuel cell

Solar Cell A cell that converts sunlight into electrical energy.

Solar panels

5. What is an electrolyte? Explain the function of an electrolyte in a cell.

• An electrolyte is a solution or paste that conducts charge.

• Electrons flow from one electrode to the other outside of the battery, while inside the battery the circuit is closed by the electrolyte's ions.