Chemistry 1 Flashcards
The Greek philosopher that believed that all matter consisted of very small indivisible particles he called atomos:
Democritus
Which of the following is not part of Dalton’s Atomic Theory:
Atoms of a given element show small differences in mass.
Different samples of the same compound always contain its constituent elements in the same proportion by mass:
Law of definite proportions
Matter can be neither created or destroyed:
Law of Conservation of Mass
The scientist who determined the magnitude of the electric charge of the electron was
Millikan
Credited with the discovery of the electron:
Thomson
Rutherford’s gold foil experiment lead to the discovery of which of the following
nucleus, protons
what is amu?
atomic mass unit
where are protons found?
nucleaus
proton mass and charge?
1 amu and 1 positive charge
where are neutrons found?
nucleus
neutron mass and charge?
1 amu and neutral charge
where are electrons found?
outside the nucleus
electrons mass and charge?
0 mass and 1 negative charge
mass number
protons + neutrons
charge
protons - electrons (never hidden)
isotope
atoms of the same element with different # of neutrons (different mass numbers)
element
anything with one type of atom
atom
basic unit of an element that is entered through a chemical combination (cannot be broken up)
molecule
two or more atoms (that can be the same or different) chemically bonded, all molecules aren’t compounds
compound
two or more different atoms chemically bonded, all compounds are molecules
ion
any atom that gained or loss electrons
diatomic molecules
elements with two or more of the same atoms (only 7 elements)
ionic compounds
metal (loses electrons and becomes positive) + nonmetal (steals electrons and becomes negative) metal is always first
covalent compound
nonmetal + nonmetal, share an electron = no charge
Dalton’s theory
elements are composed of small particles called atoms, all atoms in a given element are identical, and have the same size, mass, and chemical properties
Law of Multiple Proportions
if 2 elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in ratios of small whole numbers
Law of Conservation of Mass
matter can be neither created or destroyed. Matter is made up of atoms that are unchanged in a chemical reaction, it follows that mass must be conserved as well.
What particle(s) are found in the center of the atom?
protons and neutrons
Who discovered the neutron by bombarding a thin sheet of beryllium with alpha particles:
Chadwick
If atoms contain charged particles, why is the atom neutral?
They contain the same number of protons as electrons
What is the atomic number equal to?
the number of protons in the nucleus
What characteristic of an element varies between isotopes?
Mass Number
Which particle(s) determine the name of the element?
protons and neutrons
radiation
the emission and transmission of energy through space in forms of waves
J. J. Thomson
used a cathode ray tube to determine the ratio of electric charge to the mass of an individual electron. discovered the electron
Millikan
succeeded in measuring the charge of the electron with great precision. Proved that the charge on each electron was exactly the same. He examined the motion of single tiny drops of oil that picked up static charge from ions in the air. He suspended the charged drops in the air by applying an electric field and followed their motions through a microscope
rutherford
found protons and the nucleus
Chadwick
founded neutrons
periodic table
a chart in which elements having similar chemical and physical properties are grouped together
periods
Horizontal rows
groups/families
vertical columns
alkaline metals
first column except H
alkaline earth metals
second column
halogens
17th column until At 85
noble gases
18th column until Rn 86
