Atom, Molecules, And Ions Flashcards
Group 1A
Alkaline Metals (1+) -highly basic -React rapidly with water - never found in pure state in nature
Group 2A
Alkaline earth meals
(2+)
-less reactive
-never found in nature in pure state
Groups 3-12 (3B-2B)
Transition metals
Group 17 (7A)
Halogens
(-1)
-colorful, corrosive nonmetals
-not found in pure state in nature
Group 18 (8A)
Noble gasses
-colorless gasses with very low chemical reactivity
Metals
- all except mercury are found at room temp.
- malleable
- good conductors
Non-metals
- All on right side of zig-zag line, except Hydrogen
- when solid…
- Brittle, poor conductors
Metalloids
-properties are intermediate between those of metals and nonmetals
Intensive property
Does not depend on amount
- density
- melting point
Extensive property
Does depend on amount
- length
- volume
Physical properties
Does not involve change in chemical makeup
Chemical property
Does involve change in chemical makeup
Atoms of different elements joined together in many different ways
Chemical compound
Each chemical compound is described by its…
Chemical formula
A chemical reaction is written via a…
Chemical equation
Law of Mass conservation
Mass is neither created nor destroyed in chemical equations
Law of definite proportions
Different samples of a pure chemical compound always contain the same proportion of elements by mass
Law of multiple proportions
Elements can combine in different ways to form different chemical compounds whose mass ratios are simple, whole-number multiples of each other
Cathode ray tubes/Thomson
Discovery of electrons
Gold foil/Rutherford
Discovery of Protons and Neutrons
Dalton’s theory of matter
- elements are made of tiny particles called atoms
- each element is characterized by the mass of its atom
- fractional parts of elements are never involved in chemical reactions
- Chemicals only rearrange, atoms themselves do not change
Atomic Number
- Number of protons in nucleus
- number of electrons in neutral form
Mass number
of protons + # of Neutrons
Writing mass and atomic # together in the elemental symbol
Mass # = superscript
Atomic # = subscript
Atomic weight
Weighted average of the elements naturally occurring isotopes
Mole and Molar Mass
One mole of any element is the amount whose mass in grams (molar mass) is equal to its atomic weight
Avogadro’s Number
- 022141x10^23
- equal to the amount of atoms in 1 mol of any element
Covalent bond
- sharing electrons
- creates a molecule
diatomic elements
- only exist in pairs of themselves
- 7 to heaven
- H, N, O, F, Cl, Br, I
Binary Ionic compounds
- only 2 elements
- gain or loss of electrons
- involve cation (+) and anion (-)
- naming…
- positive ion first, name does not change
- negative ion 2nd, ending of element changes to “-ide”
Cations & Anions
- metals tend to form cations
- nonmetals tend to form anions
- find charge using location (group) on periodic table
(1+) (2+) (3+) (3-) (2-) (1-)
!!!!!
- using Roman numerals to create a neutral compound
- all about charges, an number of each element
- cross drop
Polyatomic ions
-first cation, then anion
-usually end in “-ite” or “-ate”
Oxoanions- has different # of oxygen atoms
Finding AMU using isotopes
(M1P1 + M2P2 +…) / # of isotopes
M= mass of isotope P= percent abundance of isotope (decimal)
