Chapter 2 Flashcards
Atom
A particle that consists of a nucleus of protons and neutrons surrounded by electrons.
The basic building block of all matter.
Proton
A subatomic particle within the nucleus of an atom.
Charge: +1
Mass: 1amu
Neutron
A subatomic particle within the nucleus of an atom.
Charge: 0
Mass: 1amu
Electron
A subatomic particle that orbits the nucleus of an atom.
Charge: -1
Mass: ~0
Nuclear Symbol
X = The atomic symbol
Z = Mass (# of protons + neutrons)
A = Atomic number (# of protons)
Metals
Left side of the periodic table
Highly reactive because they have many free electrons.
Ions
An atom or molecule that has a net electrical charge due to an imbalance of protons vs electrons.
Cations
Positive ions
Group 1A + 2A
Anions
Negative ions
Non-metals
Group 6A, 7A
Groups
Vertical columns of the periodic table that share chemical and physical properties
Periods
Horizontal rows of the periodic table that denote the number of electron orbitals.
Alkali Metals
Group 1A (Except Hydrogen)
Alkali Earth Metals
Group 2A
Transition Metals
Group 1B - 8B
Which group is most stable?
Group 8A
This group has a full valence shell, they will not gain or lose electrons easily.
Halogens
Group 7A
Which group is least stable?
Group 1A
This group only has one valence electron, which means they are likely to lose it.
Group Valence Electrons
Each group denotes the number of valence electrons. This is why group 8A is most stable, because they have a complete valence shell of 8 electrons.
Groups with +1 charge
Group 1A
Groups with +2 charge
Group 2A
Groups with +3 charge
Group 3A
Groups with -1 charge
Group 7A
Groups with -2 charge
Group 6A
Groups with -3 Charge
Group 5A
Groups with -3 Charge
Group 5A
Groups with 1 valence electron
Subgroup 1A
Groups with 2 valence electrons
Group 2A + All B Groups
Groups with 3 valence electrons
Group 3A
Groups with 4 valence electrons
Group 4A
Groups with 5 valence electrons
Group 5A
Groups with 6 valence electrons
Group 6A
Groups with 7 valence electrons
Group 7A
Groups with 8 valence electrons
Group 8A
Isotope
An element with a different number of neutrons than usual.
Isotopes are identified by their mass number.
Ne-21 = 10 protons + 11 neutrons
Ne-22 = 10 protons + 12 neutrons
Compound
Composed of two or more different elements and always contains exactly the same relative masses of those elements.
Chemical formula
Expresses the types of atoms and number of each type in a given compound.
For any formula containing carbon the order is carbon first, hydrogen second, and the rest in alphabetical order.
For non-carbon formulas, all elements are listed in alphabetical order.
Ionic compound formula
Ionic compounds are electrically neutral
The cation element component comes first, with the anion element component after.
Mg²⁺ + Cl⁻ + Cl⁻ = MgCl₂
Dalton’s Atomic Theory
- Elements are composed of atoms
- All atoms of an element are identical
- Atoms combine to form compounds
- Chemical reactions are rearrangements of atoms
Thompson’s Theory
- Proved the existence of electrons
- Speculated the existence of positive charge as atoms are of neutral charge
- Electrons are negative charges held within a positively charged sphere.
Rutherford’s Interpretation
- Atoms contain a dense center called the nucleus
- Protons are positively charged particles within the nucleus
- Equal number of protons and electrons
- Electrons move around in the empty space of the atom surrounding the nucleus.
- The nucleus has essentially the entire mass of the atom
- Neutrons are of neutral charge and within the nucleus.
Diatomic Elements
Rule of 7:
* Hydrogen
* Start at the element with the atomic number 7 (Nitrogen)
* Include the elements 3 across up to group 7A, 4 down to “trace” the number seven.
- Hydrogen (H₂)
- Nitrogen (N₂)
- Oxygen (O₂)
- Fluorine (F₂)
- Chlorine (Cl₂)
- Bromine (Br₂)
- Iodine (I₂)
Formula To Name: Ionic Compounds
Type I: Ions with one possible charge
Cation name + Anion name + ide
Example: CaS is Calcium Sulfide
Type II: Ions with more than one possible charge. These are the transition metals (groups 1B-8B). Determine the cation charge by finding the anion charge that balances it.
Cation name + Cation Charge + Anion name + ide
Example: CuCl is Copper (I) Chloride
Cl has a charge of -1 so the copper must have a charge of +1 to balance this.
Polyatomic Ions
Groups of atoms with a net charge.
