Development of the Atom
This scientist proposed that atoms are indivisible and combine in whole-number ratios.
Who is John Dalton?
This scientist is credited with organizing the first periodic table by atomic mass.
Who is Dmitri Mendeleev?
Electronegativity decreases in this direction due to increased nuclear charge
What is down a group?
The subatomic particle with a positive charge found in the nucleus.
What is a proton?
This equation relates the speed of light, wavelength, and frequency.
What is c = λν?
The SI unit for the amount of substance is called this.
What is the mole?
This model described atoms as a sphere of positive charge with electrons scattered throughout.
What is the Plum Pudding Model?
The modern periodic table is arranged by this atomic property.
What is atomic number?
The energy required to remove an electron from an atom is known as this.
What is ionization energy?
The subatomic particle with no charge found in the nucleus.
What is a neutron?
This equation relates the energy of a photon to its frequency.
What is E = hν?
One mole contains this many particles.
What is 6.022 × 10²³ (Avogadro’s number)?
The gold foil experiment led this scientist to discover the nucleus.
Who is Ernest Rutherford?
The periodic law states that chemical and physical properties of elements repeat when elements are arranged by this.
What is increasing atomic number?
Metals become more reactive going down this group also known as group 1.
What are the alkali metals?
The mass of an atom is mostly due to these two particles.
What are protons and neutrons?
Light is emitted when electrons move in this direction relative to the nucleus.
What is from higher to lower energy levels?
The process where an unstable nucleus emits particles or energy.
What is radioactive decay?
This model proposed electrons orbit the nucleus in fixed energy levels.
What is the Bohr Model?
Gaps in Mendeleev’s table led to the prediction of these.
What are undiscovered elements?
Nonmetals become more reactive going up this group, also known as group 17.
What are the halogens?
This term describes atoms of the same element with different numbers of neutrons.
What are isotopes?
The distinct set of lines produced when electrons return to lower energy states is called this.
What is an emission spectrum?
This type of nuclear reaction splits heavy nuclei into smaller ones.
What is fission?
This principle states that it is impossible to know both the position and momentum of an electron simultaneously.
What is Heisenberg’s Uncertainty Principle?
This scientist’s arrangement of the periodic table explained periodic trends based on electron configurations.
Who is Henry Moseley?
This property describes the energy change when an atom gains an electron.
What is electron affinity?
The weighted average of all isotopes of an element is called this.
What is average atomic mass?
This model shows electrons in regions of probability called orbitals.
What is the Quantum Mechanical Model?
This type of reaction combines light nuclei to form heavier ones.
What is fusion?