Atomic Theory Flashcards
What three things does the basic atom consist of?
Protons, neutrons in the nucleus and electrons that orbit the nucleus
What model shows the electrons orbiting the nucleus ?
Bohrs model
What charge does a proton have?
Positive and weight
Neutrons have what charge?
No charge but have weight
Electrons have what charge?
Have a negative charge and negligible weight
What is shell furthest from the nucleus called?
Valence Shell- can hold maximum of eight electrons
What are the valence electrons key to?
Whether it can or cannot conduct electrical current
What five states does matter exist in?
Bose-einstein condensates Solid Liquid Has Plasma
What are three classifications of matter
Conductor
Semi-conductor
Insulator
What can the valence electron do?
Easily break free to combine with neighbouring atom
How many electrons do conductors have in the atoms orbit?
3 or less
How does the movement of electrical charge work?
When the protons equals the number of electrons
Like charges do what?
Repel
Unlike charges do what?
Attract
External forces can cause the valence electron to break away leaving it positively charged, this atom is now what?
Positive ion
Free electron may join the valence electron electron to balance another atom, this is called?
A negative ion
What do electrons flow from and to?
From a surplus (-) charged ion to a deficient (+) charged ion , if they have a voltage behind them
What is electron flow ?
Random movement = no electron flow or no electric current flow
What is the minimum values for DC and AC volts?
DC - 120 volts
AC- 50 volts
How many Atoms can the valence hold in insulators?
Maximum of 8 electrons , generally more than 4 electrons
What are covalent bonds?
Each atom gives one of its outer electrons to the electron pair, then spends some time with each atom
What is the insulation breakdown effect ?
When enough pressure and voltage is applied to conduct electricity in insulators
What are semi conductors ?
Contain exactly 4 electrons in the atoms outer orbit
3 effects of electrical current
Heating
Magnetic
Chemical
What is the heating of electrical current ?
When electrical current is passed through a metallic causing it to become heated
