Matter And Particles Flashcards
Describe particle arrangement in a solid
Particles are: Tightly packed Regular arrangement Vibrate in fixed positions Strong forces hold particles in place
Definite shape
Definite volume
Describe particle arrangement in liquids
Particles are: Tightly packed Irregular arrangement Slide over each other Forces weaker than solids
Change shape to take the shape of container
Definite volume
Describe particle arrangement in gases
Particles are Far apart
Move very fast and randomly
Very Weak forces
Take up whole container
No definite volume
Describe what happens when you melt a solid
Heat energy given to particles
Particles vibrate faster
And release from their fixed positions
Solid melts
Describe what’s happens when you evaporate a liquid
Heat energy given to particles
Particle move faster
Particles gain enough energy to escape from the liquid
What is melting point?
Temperature at which a substance changes from solid to liquid
What is boiling point?
Temperature at which a substance changes from liquid to gas
What is diffusion?
The net movement of particles from high concentration to low concentration
E.g. Bromine gas (brown)
Potassium manganate crystals in water
What is Brownian motion?
Proves existence of moving particles.
Under microscope, smoke particles moving random and jerky
Because invisible air particles are colliding with them.
Name the parts of an atom.
Protons and neutrons in a nucleus
Electrons in shells orbiting nucleus
What is the charge on a proton?
1+
What is the charge on a neutron?
0
What is the charge on an electron?
1-
What is the mass of a proton?
1
What is the mass of a neutron?
1
What is the mass of an electron?
1/1836
What is atomic number?
Number of protons
What is mass number?
Number of protons + neutrons
It is the RAM (relative atomic mass)
In a neutral atom, number of electrons =
Number of protons
How do you calculate number of neutrons?
Mass number -atomic number
What is an isotope?
Atoms with the same number of protons but different number of neutrons
How do you calculate relative atomic mass ( RAM)?
eg (0.73 X mass number A) + (0.27 X mass number B)
What is the electronic configuration of the first 3 full shells?
2, 8, 8
What is an element?
Pure substance containing one type of atom
What is a molecule?
Atoms joined together.
Can be same type or different type of atoms
What is a mixture?
Two or more substances mixed but not chemically joined
Easy to separate
