Matter
Anything that takes up space and has mass
elements
Substances that cannot be broken down into simpler substances by normal means (Hydrogen)
Compounds
Substances composed of atoms of two or more substances (H2O)
CHNOPS
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorus
Sulfur
Atom
The smallest particle of an element that has the element’s properties. Subatomic particles.
structure of an atom
Protons +
Neutrons 0
Electrons –
Protons and Neutrons in the positively charged Nucleus, then Electrons orbit around it on the E- shells.
atomic number
: Number of protons, defines an element
Mass number
Protons + Neutrons, size of nucleus
Isotopes
Same element with a different number of neutrons.
unstable (radioactive) isotopes
Unstable isotopes undergo radioactive decay
Radioactive
: Nucleus releases energy or particles (Alpha, Beta, Gamma)
Half-Life
The time it takes for 50% of the radioactive sample decay
real-world applications of isotopes
- Sterilization
- Cancer tracers
- Evidence of climate change
how electrons are arranged in energy levels
Electrons orbit around nucleus on e chells
maximum number of electrons that can occupy each e shell
1st chell max=2
2nd and 3rd chell max= 8
Vallance Shell
The shell that is furthest away from the nucleus
Valence Electrons
The e’s in the Valance shell
why atoms with incomplete valence shells are more chemically reactive
They seek out other atoms to share or exchange electrons with
three ways atoms interact with electrons during bond formation
- Give away an electron
- Gain an electron
- Share an Electron
Ion
Charged particle
Cations
+ charge
Anions
- Charge
how ionic bonds form
One atom gives an electron, and one atom accepts it into its valence shell
which atoms would be more or less likely to form ionic bonds.
