Chapter 2 Vocabulary Flashcards
all matter is composed of atoms
Atomic Theory
in a chemical reaction, matter is not created nor destroyed
Law of Conservation of Mass
all samples of a given compound, regardless of their source, have the same proportions of elements
Law of Definite Proportions
When 2 elements (A&B) form two different compounds, the masses of element B that combine with 1g of element A can be expressed as a ratio of small whole number.
Law of Multiple Proportions
- each element is composed of tiny indestructible particles called Atoms
- all atoms of a given element have the same mass and other properties that distinguish them from other atoms
- atoms combine in simple whole numbers
- atoms of one element cannot change into another
Dalton and Atomic Theory
- most of an atom’s mass and all of its positive charges are in a small core called nucleus
- most of the atom is empty space with negatively charged electrons
- number of electrons = number of protons. matter is neutral
Nuclear Theory
defined by the number of protons
Matter
Positive ions (loss of electrons) are called
Cations
Negative ions (gain of electrons) are called
Anions
good conductors, malleable (loses elections)
Metal Properties
poor conductors, not malleable (gains electrons)
Nonmental Properties
more predictable
main group elements
less predictable
transitional elements
Group 1A - very reactive (+1)
Alkali Metals
Group 2A - fairly reactive (+2, except 1st element)
Alkaline Earth Metals
