Chemistry Flashcards
Fundamentals of chemistry
Atoms
Definition + components
The most basic unit of all matter. Neucleus surrounded by subatomic particles.
Subatomic particles
List them
- Protons
- Neurons
- Electrons
Protons
charge / mass / location on atom
Subatomic particle
+1 charge / 1 mass / stuck in the in nucleus
* Number dictates it’s element
Electrons
Subatomic particle
-1 charge / «<1=0 / travels around the nucleus
- moves easily between atoms
- charge changes when added or removed
Neurons
Subatomic particle
0 charge / 1 mass / stuck in the nucleus
What is the charge of an atom?
protons - electrons
= charge
What is the mass of an atom?
of protons - # of neurons
= mass
What are elements?
Different types of atoms that have different chemical properties.
The # of protons determines what element an atom is and the charge of its nucleus.
The # of neurons and electrons can be different between different atoms of the same element.
Periodic table of elements
Table that shows all elements known to man, each square is a different element.
Contains:
* Name of element (not always)
* Atomic # = # of protons in the nucleus
* Atomic symbol = 1 capital letter or 1 capital + 1 lower case
* Atomic mass = mass of atom, #protons + #neurons
Electron Shells
3 orbiting shells of electrons around the nucleus.
1st shell has 2 electrons
2nd shell has 8
3rd has 8
What do atoms want?
2 things:
1. The outer shell to be full
2. A neutral charge (# of protons = # of electrons)
What are right column atoms?
Noble gasses
Generally don’t interact with other elements & have a full outer shell (same # of protons and electrons)
What are ions?
Atoms on a small molecule with an electrical charge.
The # of protons + electrons are different but make a full outer shell.
Anions
Ions with a negative cahrge.
protons < electrons
Cations
Ions with a positive charge
protons > electrons
Ionic bond
When possitive and negative ions attract and form a bond.
(-)Anion + (+)Cation –> negative attracts positive
ex: table salt - NaCl
List of important ions
Name + Periodic lable
- Sodium - Na+
- Chloride - Cl-
- Potassium- K+
- Calcium - Ca++
- Magnesium - Mg ++
- Iron - Fe (2+ or 3+)
What is a covalant bond?
2 atoms held together by sharing electrons.
This allows atoms to have a full outer shell with a neutral charge, forming a bond stronger than ionic bonds.
Single bond
2 atoms sharing 2 electrons
ex: H-H / H-O-H
Double bond
2 atoms sharing 4 electrons
ex: O=O (molecular oxygen)