Chapter 3 Flashcards
Proposed the atomic theory in 1803
John Dalton
All matter is composed of atoms; Atoms of the same element are identical in properties; Atoms cannot be created, subdivided, or destroyed; Atoms of different elements combine to form compounds; In chemical reactions atoms are combined, divided, or rearranged.
Dalton’s Atomic Theory
Matter cannot be created or destroyed but can only change forms.
Conservation of Mass
2 or more different compounds are composed of the same 2 elements then the masses of the 2nd element combined with a certain mass of the 1st element can be expressed as a ratio of whole numbers.
Law of multiple proportion
Identity and arrangement of smaller particles within the atom
Atomic Structure
Hold protons and neutrons together inside the nucleus.
Nuclear Forces
Atoms of the same element that have different masses.
Isotopes
The number of protons in the nucleus of each atom of that element.
Atomic Number
The total number of protons and neutrons in the nucleus of that element.
Mass Number
The general term for any isotope of any element.
Nuclide
Exactly 1/12 of the mass of carbon-12 or 1.6605655 E -24
Atomic Mass Unit (amu or u)
The weighed average of the atomic masses of the naturally occurring isotopes of the element.
Average Atomic Mass
The amount of substance that contains the same number of particles as the number of atoms in exactly 12g of carbon-12
Mole
(6.02 E23) the number of particles in exactly one mol of pure substance.
Avogodro’s Number
The mass in grams of one mol of an element
Molar Mass
