Studied by 6 people
atomic number
Elements on modern periodic table are arranged in order of increasing _____________
Period
horizontal row, numbered 1-7 (except for f-block)
Group or Family
vertical columns, numbered 1-18
Inner transition metals
f-block, lanthanide series and actinide series
Main group or Representative elements
elements in tall columns (s- and p-blocks)
properties
Modern periodic table is based on _____________
Transition elements
d-block and f-block
Metals
gray/silver, shiny, malleable, ductile, good conductors, solids (left of the stair step line)
Alkaline earth metals
group 2
Properties
behaviors or characteristics
Transition metals
groups 3-12, d-block
Bromine
_____________ is a nonmetal liquid
Lanthanide series
elements 57-71
Nonmetals
variety of colors, gasses, brittle, dull-looking solids, insulators, poor conductors of electricity and heat, located to the right of the stair step line (includes hydrogen)
similar valence electrons
Elements in groups have the same properties because they have _____________
Alkali metals
group 1 (excluding hydrogen), reactive
Magnesium and Calcium
_____________ and _____________ compounds are important nutrients for people
Atomic radius
the distance from the center of the nucleus to the most probable location of the outermost valence electron in an atom, unit is picometer
Oxygen
_____________ is the most abundant element in the human body
Halogens
group 17, usually found as parts of compounds
fluorine
Compounds of _____________ are used to prevent tooth decay
Noble gases
group 18, unreactive, used in lasers, light bulbs, and neon signs
Metalloids
properties of both metals and nonmetals, used in computer chips and solar cells
the same number of valence electrons
Atoms in the same group have similar chemical properties because they have _____________
Ionization energy
required to remove an electron from one mole of a gaseous substance
electron configurations
Element properties come from their _____________
Ions
charged particles formed when an atom or a group of atoms loses or gains electrons
Actinide series
elements 89-103
Cations
positively charged ions formed by losing electrons, smaller than their neutral atoms, largest ionic radii are at the bottom left (metals)
Anions
negatively charged ions formed by gaining electrons, larger than their neutral atoms, largest ionic radii are at the bottom left (nonmetals)
Mercury
_____________ is a silver-colored, metal liquid
stable
Ions are made to form more _____________ electron configurations
bottom left
Atomic radii are greatest toward the _____________
Ionic radius
the distance from the center of the nucleus to the most probable location of the outermost valence electron in an ion, unit is picometer
Low electronegativity
little attraction for electron in bond
First ionization energy
the energy required to remove the most loosely bound electron (outermost valence electron) from a gaseous atom, turning it into a cation with a 1+ charge, symbol: I1 or IE1, unit: kJ/mol
Ionization energy is low
electron is easily removed
Ionization energy is high
electron is difficult to remove
top right
First ionization energies are greatest toward the _____________
Electronegativity
the relative tendency of an atom to attract the electrons involved in a chemical bond with another atom, unit-less number ranging from 0-4, greatest values are toward top right, not defined for noble gases
High electronegativity
strong attraction for electron in bond
Octet rule
states that atoms tend to gain, lose, or share electrons until they achieve a stable electron configuration, usually one with 8 valence electrons or a full valence shell of electrons
Chemistry
the study of matter and the changes it undergoes
Matter
anything that has mass and takes up space
Pure substance
matter that has a definite composition, a chemical formula
Element
pure substances that cannot be broken down into simpler substances by physical or chemical means
Atom
the smallest particle of an element that retains all the properties of the element
Modern Atomic Theory
All matter is composed of small, divisible particles called atoms. Not all atoms of the same element are identical (isotopes). Atoms of different elements are different. Atoms can bond with one another in simple ratios to form compounds.
Subatomic particles
particles smaller than atoms (proton, neutron, electron)
Atomic mass unit
unit of mass for expressing masses of atoms or molecules; 1/12 of the mass of an atom of carbon-12
Nucleus
located in the center of the atom, small in volume, positively charged, contains most of the atom's mass
Electrostatic attraction
the attraction between oppositely charged particles (negative electrons to positive protons)
Electron
symbol: e-, charge: 1-, mass: 0 amu, location: empty space around nucleus/ electron cloud
Proton
symbol: p+, charge: 1+, mass: 1 amu, location: nucleus
Neutron
symbol: n0, charge: 0, mass: 1 amu, location: nucleus
Atomic number
the number of protons in an atom, symbol: Z, whole number located in the box, makes an element a particular element.
Isotopes
atoms with the same number of protons, but different numbers of neutrons, same element that differ in mass number
Mass number
the sum of the number of neutrons and protons in an atomic nucleus, symbol: A, NOT on most periodic tables
Atomic mass
the weighted average mass of the naturally occurring isotopes of an element, (%)(mass) + (%)(mass) + ...
Radioactivity
the spontaneous emission of radiation
Radiation
energy rays and/or particles
Radioactive decay
to fall apart by giving off nuclear radiation, until they become stable
Ratio of neutrons to protons
what determines the stability of an atomic nucleus
Nuclear reaction
the atom's nucleus changes, often turns into a different element
Nuclear equation
symbolizes a nuclear reaction
Alpha radiation
helium-4, consisting of 2 protons and 2 neutrons, mass: 4 amu, charge: 2+
Beta radiation
a high-speed electron emitted from a radioactive nucleus, mass: 0 amu, charge: 1-
Gamma radiation
a high-energy form of electromagnetic radiation, has no mass and no charge, not a particle, just energy
Fission
a neutron slams into a larger atom, forcing it to split into two smaller atoms (splits)
Fusion
two atoms slam together to form a heavier atom (fuse)
Law of Conservation of Mass-Energy
mass and energy can be converted from one to the other, but their sum remains constant
Circle graph
shows the parts of a whole/ percentages
Bar graph
evaluates trends in a measured property often as a function of time, location, or temperature
Line graph
determines property trend or the mathematical relationship between two variables
Direct relation
positive slope, straight line
Indirect relation
negative slope, straight line
Inverse relation
hyperbola, a curve with a negative slope that never crosses an axis
Electromagnetic radiation
a form of energy that exhibits wavelike behavior as it travels through space
Wavelength
the shortest distance between 2 equivalent points on a continuous wave
Units for wavelength
meter or nanometer
Symbol for wavelength
lambda, λ
Frequency
the number of waves that pass a given point per second
Unit for frequency
hertz, 1/s
Symbol for frequency
nu, ν
Amplitude
the wave's height from the origin to a crest or trough
Speed of light equation
c (speed of light, m/s) = λ (wavelength, m or nm) * ν (frequency, hertz)
inversely
Wavelength and frequency vary ________.
Electromagnetic spectrum
a spectrum that includes all forms of electromagnetic radiation
Quantum theory
a theory created by Max Planck to explain how matter lost and gained only small, specific amounts of energy
Quantum
the minimum amount of energy that can be lost or gained or gained by an atom
Photon
a particle-like bundle of energy without mass that carries a quantum of electromagnetic energy
Energy of a photon equation
E (energy, joules) = h (Planck's constant, joules * seconds) * ν (frequency, hertz)
Spectroscopy
the method of studying substances exposed to energy
Spectrum
the pattern of energy studied in spectroscopy
Atomic emission spectrum
the set of frequencies or wavelengths of the electromagnetic waves emitted by atoms of the element
unique
Each element produces a ________ line spectrum.
Bohr's (planetary) model
an early atomic model of the hydrogen atom that was developed by studying the emission spectrum of hydrogen
Accurate part of Bohr's model
the electron can only posses certain quantities of energy/ have certain allowed energy states
Ground state
the lowest and most stable energy state
Excited state
any state of energy that is more than the lowest amount
