Chem Quiz #1 Flashcards
(56 cards)
What is the Atomic Theory?
Atomic theory is the scientific theory that matter is composed of particles called atoms
Dalton’s Atomic Theory
- all matter is composed of tiny, individual particles called atoms
- atoms of an elemnet have identical properties
- atoms of different elements have different properties
- atoms of two or more elements can combine in constant ration to form a new substance
J.J. Thompson’s Atomic Theory
Raisin Bun
- discovery of electrons
- raisun bun or plum pudding model
- atom is sphere which is positive, with negative electrons embedded in it like raisins in a bun
- most of the mass is associated with the psotive charge
Ernest Rutherford’s Atomic Theory
Nucleus
- atoms have a nucleus which is positive and has most of the mass
- most of the atom is empty space, occupied by the moving negatively charged atoms
- propsed the existence of protons
Neils Bohr’s Atomic Theory
Planetary Model
- electrons move in circular orbits around the nucleus
- cannot exist between orbits
James Chadwick’s Atomic Theory
Neutrons
- showed that the nucleus mus contain heavy neutral particle to account for all of the atom’s mass (neutrons)
Schrodinger/de Broglie’s Atomic Theory
Quantum Model
- Quantum Mechanical model
- electrons have distinct energy levels
- exact location of electrons are not defined, but the probable reaction in a region of space can be predicted
What is a Proton?
- positive charge subatomic particle
- found in nucleus
- determines the type of element
What is a Neutron?
- neutral charge subatomic particle
- found in nucleus
- used to hold nucleus together
What is an Electron?
- smallest subatomic particle
- negative charge
- found in “cloud” region
- arranged in energy levels
What is Atomic Mass?
- AMU is the mass of a proton or neutron = 1.7 x 10 to the power of -24g
- net charge for all atoms is 0
- e- = #p+ in a neutral atom
- mass number is the sum of protons and neutrons (rounded to nearest whole number)
- used to find the number neutrons
What is an Isotope?
- atoms that have same number of protons but a different number of neutrons
- atomic mass on the periodic table is an average mass based on the % abundances of all naturally occuring isotopes of the element
- provide atomic mass in the name
The Periodic Table
- Metals
- Non Metals
- Metalloids along stair case
What is the Atomic Number?
- number of protons in one atom of an element
- increases from left to right and top to bottom
What are the properties of Metals?
- good conductors
- strong
- malleable
- ductile
- high lustre
- are found on left side of staircase
What are the properties of Non-Metals?
- poor conductors
- non lustrous
- weak
- non ductile
- non malleable
- opposite properties of metals
- found on right side of staircase
What are the properties of Metalloids?
- shows properties of both metals and non metals
- found along the stair case
How many groups are there in the Periodic Table?
- 18 vertical groups called families
- labelling system: Roman Numeral and letters or ordinary numbers
What is Group 1 (IA)?
Alkali Metals (very reactive)
What is Group 2 (IIA)?
Alkaline Earth Metals (less reactive)
What is Group 17 (VIIA)?
Halogens (reactive non metals)
What is Group 18 (VIIIA)?
Inert or Noble Gases (unreactive)
What is the Lanthanide Series (IA)?
Rare Earth (57-71)
What is Group 3-12 (B Series)
Transition Metals
