Atomic Theory
This scientist proposed that atoms are solid spheres that cannot be divided.
Who is John Dalton?
This subatomic particle is positively charged and found in the nucleus.
What is a proton?
Atoms of the same element with different numbers of neutrons.
What are isotopes?
The time required for half of a radioactive sample to decay.
What is a half-life?
Vertical columns on the periodic table are called this.
What are groups?
The scientist who discovered the nucleus through the gold foil experiment.
Who is Ernest Rutherford?
A neutral particle located in the nucleus.
What is a neutron?
An atom or group of atoms with a net electric charge.
What is an ion?
The emission of particles and energy from an unstable nucleus.
What is radioactivity?
Horizontal rows on the periodic table are called this.
What are periods?
These scientists suggested that the location of electrons are not truly known.
What is Heisenberg and Schrodinger?
A negatively charged particle in the electron cloud.
What is an electron?
The weighted average mass of all isotopes of an element.
What is the average atomic mass?
The process of splitting a large nucleus into smaller ones.
What is nuclear fission?
Elements with the same number of valence electrons belong to the same ___.
What is a group?
Electrons in the outermost energy level are called this.
What are valence electrons?
The force that holds protons together in the nucleus despite their repulsion.
What is the strong nuclear force?
The mass number of an atom is calculated by adding these two subatomic particles.
What are protons and neutrons?
The combining of light nuclei to form a heavier nucleus.
What is nuclear fusion?
Noble gases are stable because they have full ___.
What are energy levels or valence shells?
Fundamental particles making up protons and neutrons.
What are quarks?
The number of protons in an atom is given by this piece of the periodic table.
What is the atomic number?
This term refers to isotopes that are unstable and emit radiation due to excess nuclear energy.
What are radioactive isotopes?
This type of decay causes skin burns and can travel 2-3m.
What is beta decay?
The first group in the periodic table is known as this.
What are alkali metals?