Week 1 Flashcards
Matter
Anything that occupies space and has a mass
All matter is made up of particles
The particle theory of matter explains that
The particles in each different state (solid, liquid, gas) behave differently
Solids
Particles packed together in a fixed 3D lattice
Attractions between particles very strong (higher melting point)
Particles vibrate but don’t move out of fixed positions
The higher the melting point…
The stronger the bonds between the particles
Liquids
Particles are disordered and collide into each other and walls of the container.
Volume remains constant
Gases
Particles far apart and disordered
Particles collide into each other and the walls of the container
Volume isn’t constant
Mass
Measure of the quantity of matter in an object regardless of gravity force
Weight
The force that gravity exerts on an object
Substance
A form of matter that has a constant composition and distinct properties
Can write a chemical formula
Mixture
A combination of two or more substances.
Do not have a constant composition.
Cannot write a chemical formula
Atoms
All matter is composed of atoms
Element
A substance composed of only one type of atom
Compound
A substance composed of two or more different types of atoms
Protons and neutrons…
Have roughly the same mass (1)
Subatomic particles
Protons, neutrons and electrons
Atomic number
Number of protons in the nucleus of each atom of an element
Determines the chemical identity of an atom
Isotopes
Atoms that have the same atomic number but different mass numbers
Isotopes of the same element have similar characteristics because neutrons do not take part in chemical reactions
Chemical properties of an element
Protons and electrons determine the chemical properties of an element
Neutrons do not take part in CHEMICAL reactions
Masses of subatomic particles
E-1/1836
P-1
N-1
Similarities of isotopes
Atomic number
Chemical properties
Number of electrons
Differences of isotopes
Mass number
Number of neutrons
Stability of nucleus
