Elements Flashcards
(25 cards)
What are representative particles?
Atoms, molecules and formula units
A mole = _____ of representative particles
6.02 x 10^23
What is a molecule?
A compound
What is a formula unit?
A compound
What’s special about a formula unit?
It’s a compound of metals and non-metals
To find the molar mass-
Add up the atomic mass and put over 1 mole
Moles to mass
Go to grams (atomic mass)
Mass to moles
1 mole / grams
Isotopes
When the amount of neutrons is different for the same element
Atomic mass
Mass for one atom of the element
Atomic number
Number of protons and electrons
Atom
Single element
Ion
Atoms that have a positive or negative charge
Cation
Atom with a positive charge
Anion
Atom with a negative charge
Molar mass
Mass in grams of 1 mole of a substance
What did John dalton find true?
Atoms of different elements combine to make new compounds
Atoms of 1 element can’t change into a new element
JJ Thompson’s experiment-
Cathode ray tube
Discovered electron
Ernest Rutherford’s experiment-
Gold foil (they repel because of opposite charges) Discovered protons
Neils Bohr-
Discovered the 7 orbits for electrons
Sir Chadwick-
Discovered neutrons
What are the 2 parts of dalton’so theory that were proved wrong?
All matter is combined of tiny particles called atoms
All atoms of an element are identical
The volume of an atom is
The nucleus
The mass is
Protons and neutrons
