3.1 Flashcards
When is an atom negative
When there are more electrons than protons
When electrons is moved away from the atom what form of energy is produced
Electricity
What are positive and negative charged atoms called
Ions
When is an atom positive
When there are more protons and less electrons
What is a the charge of a single electron
-0.1602 X10-18 C (Coulombs)
What is the charge of a single proton
+ 0.1602 X10-18 C
When is an atom neutral
When number of protons = number of electrons
How are electrons connected in an atom for non conductor or insulator
Tightly packed and more than 4 in the outer orbit, also no free electrons
Examples of insulators or non conductors
Mica and porcelain
In insulators, what voltage is needed to take away electrons.
3V exceeding
How many electrons are shared in semiconductors
8
How is conductivity produced
By adding other foreign atoms (doping) by heat or light
Examples of semiconductors
Silicon and Germanuim
How can matter be broken down into atoms
By the use of chemicals
What are the four effects that electricity creates
Heat
Magnetic action
Light
Chemical action
Electric current is what
A flow of electrons
How many electrons in outer shell of semiconductors
4
What is a charged atom known as?
Ionised
A good conductor will have what characteristics
Less than 4 electrons in the outer orbit
High density allows what for the electrons
To separate and move freely
Do electrons have a mass
No
What voltage is needed for electrons to be removed in conductors
No voltage is required
What happens to the electrons on the outer layer of a conductor due to high density
They separate and move freely
What is in the nucleus atom
Protons and Neutrons
What are positive and negative charged atoms called
Ions
Examples of conductors
Copper,aluminium and carbon
In conductor, how are the atoms arranged
Closed packed in a crystal lattice
When is an atom positive
When there are more protons and less electrons
In semiconductors what voltage is needed to remove the electrons
Less than 3V
Types of thermocouple
Alumel and chromed
