Unit D Section 1.4

Question 1

What is a pacemaker?

Answer 1

A pacemaker is an is an implanted device that delivers a small amount of current at regular intervals to keep the heart beating normally for people who have problems with heart beating.

Question 2

What is an electrochemical cell?

Answer 2

An electrochemical cell is Cells that contain chemicals to produce a steady current/electricity.

Chemical reactions produce small amounts of current.

Question 3

What are the two main cells:

Answer 3

Dry cell

Wet cell

Question 4

What are dry cells:

Answer 4

They are called dry because chemicals are in paste or powder.

Can be used in things such flashlight and radios

Question 5

What is the process of dry cells?

Answer 5

The chemicals in the cell release free electrons through the negative terminal and then through the device and back in the cell through the positive terminal.

Question 6

The most common dry cell is

Answer 6

Alkaline cells have become the most common type of dry cell.

Question 7

Structure of a cell:

Answer 7

A cell is simply two different metals in an electrolyte.

The electrolyte reacts with the two metals, called electrodes.

As a result of this reaction, one electrode becomes positively charged, and the other becomes negatively charged. These electrodes are connected to the cell’s terminals

Question 8

electrolyte

Answer 8

An electrolyte is a paste or liquid that conducts electricity because it contains chemicals that form ions.

Question 9

Ions

Answer 9

Ions n is an atom or a group of atoms that has become electrically charged through the loss or gain of electrons from one atom to another.

Question 10

In a dry cell which terminal do electrons leave?

Answer 10

In a dry cell, electrons leave from the negative electrode, and return to the positive electrode.

Question 11

What are Wet cells:

Answer 11

A wet cell uses a liquid electrolyte that is usually an acid, such as sulfuric acid.

The acidic electrolyte gradually eats away the zinc electrode. But is often replaced. This process leaves behind electrons that give the slowly disappearing electrode a negative charge

Electrons travel along the wire from the negative zinc electrode to the positive copper electrode. They provide energy

Question 12

WHich is the zinc electrode and which is the copper?

Answer 12

zinc= negative electrode copper= positive electrode

Question 13

Drawbacks of a cell:

and the solution

Answer 13

Cells tend to be heavy and rigid.

Solution: make cells out of plastic.

Question 14

primary cell

Answer 14

Primary cells are cells that produce electricity from chemical reactions that cannot be recharged or reversed.

Question 15

Are dry cell and wet cell primary or secondary cells?

Answer 15

Dry cells and wet cells are considered primary cells.

Question 16

Secondary cells

ALso known as rechargable cell:

Answer 16

Secondary cells are rechargeable cells.

A rechargeable cell can be reversed by using an external electrical source to run electricity back through the cell. This is when electrons flow is reversed and restores the reactants that are used up when the cell produces electricity.

Question 17

What are secondary or rechargeable cells used for?

Answer 17

They can be used to operate cell phones and laptops.

Question 18

combination of chemicals often used in secondary cells:

Answer 18

Nickel oxide and cadmium

This process does not reform the electrodes perfectly and rechargeable cells wear out eventually.

Question 19

What is a battery?

Answer 19

Connecting cells together creates a battery

Most batteries are sealed into cases with only two terminals

Question 20

Electrochemistry:

Answer 20

study of chemical reactions involving electricity.

Branch of science that deals with the study of electricity and the chemicals that produce electricity

Question 21

What is electrolysis?

Answer 21

Electro= electricity 
Lysis= breakdown 

Using electricity we can separate useful elements from a compound

Ex. Electrolysis of water produces the fuel for the space shuttle. The water molecules are separated into pure hydrogen and oxygen. When these two gases are mixed and ignited, they release a tremendous amount of energy, making these two elements a powerful rocket fuel.

Question 22

What is electroplating?

Answer 22

A technique of covering an inexpensive metal with an expensive metal by passing electricity

Ex. Gold trophy or spoons, cheaper metal is stronger too.

Question 23

Process of electroplating?

Answer 23

The item to be coated and a bar of the coating metal are immersed in an electrolyte, like the electrodes in a wet cell. A source of electricity is connected between the two metals. The flow of electricity through the electrolyte deposits atoms from the positively charged metal onto the negatively charged one. Electroplating is often used to protect metals from corrosion.

Question 24

Other electro things:

Answer 24

Anodizing and electrorefining are two more examples of electrochemical

Anodizing is a process to coat aluminum parts with a layer of aluminum oxide.

Electrorefining can be used to remove impurities from metal.

. For example, impure gold can be formed into bars that serve as an electrode in an electrolytic cell.