3.1 Electron Theory Flashcards
What are the three subatomic parts within an atom?
-proton
-neutron
-electron
In nature atoms and molecules are said to be electrically?
Neutral
If a atom or molecule is said to be electrically neutral, what is used to change this?
Friction
What charge does a proton hold?
A positive charge
What charge does a neutron have?
A neutral charge
What charge does an electron have?
A negative charge
Where can an electron be found in an atom?
In an orbit (shells)
What prevents the electrons from moving away the nucleus?
They’re attracted to the positively charged protons
What is the charge of a single electron?
-1.602 x 10^-19
What is the charge of a single proton?
+1.602 x 10^-19
Why do protons and neutrons make up the mass of an atom?
Because electrons have almost no mass
What is the electrical charge of an atom if it has the same amount of protons and electrons?
There is no electrical charge
If an atom has more electrons than protons, what is its electrical charge?
Negative
If an atom has more protons than electrons what is its electrical charge?
It has a positive charge
What are positive or negative charged atoms called?
Ions (positive ions or negative ions)
A charged atom is said to be?
Ionised
What is a molecule?
An electrically neutral group of two or more atoms held together by chemical bonds
What is a charged molecule called?
It is also called an ion
To detach an outer electron from an atom what is needed?
External energy (heat, light, electrostatic fields, etc)
When an electron is detached from an atom what is it called?
Free electron
When an atom losses an electron what electrical charge does it take up?
A positive ion (because it now has more protons than electrons)
When an atom gains an electron in its outer orbit it becomes?
Negatively charged because it now has more electrons than protons
What are the two ways that ions can be created?
Physically or chemical means
When two or more elements are combined chemically, what is the new substance called?
A compound
In metal the atoms are closely packed and form a giant structure with a regular pattern. What is this called?
Crystal lattice
In the crystal lattice of metals what overlaps?
The outer shells of atoms
Why do the outer shells of a crystal lattice overlap?
To allow the electrons to move freely through the lattice like a Fluid
Why are metals good conductors?
High electron mobility
What is the general rule for good conductors when it comes to electrons?
To have less than four in the valence orbit
How can a semiconductor be defined?
Somewhere between a good conductor and a good insulator
How can the conductivity of a semiconductor be affected?
Temperature, doping (adding foreign atoms), or by light
What is the general rule for semiconductors when it comes to electrons?
Contain four in the valence orbit
Where are semiconductors located in the periodic table?
In between metals and non-metals
What are insulators also known as?
Non-conductors
In insulators what prevents the electrons from breaking away?
They’re tightly connected to the atoms or molecules
What is the general rule for good insulators when it comes to electrons?
The valence orbit contains more than four electrons
What are the names for a positively and negatively charged ion?
Cation (positive) anion (negative)
