Nuclear chemistry unit 4

Protons

Subatomic particles with a positive charge.

Neutrons

Subatomic particles that carry no charge (neutral).

Nucleus

The central part of an atom, containing protons and neutrons.

Stability of an Atom

Determined by the ratio of neutrons to protons; an unbalanced ratio leads to instability.

Radioactive decay

The process by which an unstable nucleus loses energy by emitting radiation.

Role of the Neutron

Neutrons reduce the repulsive force between protons, holding the nucleus together.

Strong Force

The fundamental force that holds protons and neutrons together in the nucleus.

Fission

The process when a large atom splits into smaller atoms, releasing energy.

Nuclear Chain Reaction

A series of reactions where released neutrons from fission induce further fission.

Exponential Growth of Chain Reaction

Each fission event releases more neutrons, triggering more fission reactions and leading to rapid growth.

Fission Equation for U-235

An equation showing the fission of Uranium-235 and the conservation of matter.

Mass number

The total number of protons plus neutrons in an atom.

Atomic number

The number of protons in an atom.

Isotope

Atoms of the same element with different numbers of neutrons.

Average atomic mass

The weighted average of all isotopes of an element.

Symbol Notation

A representation of an element that includes its mass and atomic number, e.g., ^{35}_{17}Cl.

Proton Calculation

Determining the number of protons in an atom based on its atomic number.

Neutron Calculation

Determining the number of neutrons by subtracting the atomic number from the mass number.

Atomic Structure Change by Proton Addition

Adding a proton changes the element and increases the atomic number by 1.

Atomic Structure Change by Neutron Removal

Removing a neutron results in a different isotope of the same element.

Atomic Structure Change by Electron Removal

Removing an electron creates a positively charged ion.

Effect of Neutrons on Chemical Properties

Changing neutrons affects stability, but chemical properties remain consistent.

Stable Isotopes

Isotopes that do not undergo fission and are more common.

Unstable Isotopes

Isotopes that may undergo fission and are less common.

Ratio of Protons to Neutrons

The key factor determining the stability of an atom.

Nuclear Reactions vs. Chemical Reactions

Nuclear reactions release significantly more energy than chemical reactions.

Mass-Energy Relationship

Described by Einstein's equation E = mc^2, showing mass can be converted into energy.

Chemical Reaction

A process that involves the rearrangement of the molecular or ionic structure of a substance.

Energy Release in Nuclear Reactions

Nuclear reactions yield much larger amounts of energy compared to chemical reactions.

Uranium-235

A specific isotope of uranium commonly used in nuclear fission reactions.

Chain Reaction

A process in which the products of a reaction cause further reactions to take place.

Conservation of Matter

The principle stating that matter cannot be created or destroyed in an isolated system.

Energy and Mass Connection

The principle that mass can be converted to energy; as per Einstein's theory.

Neutron to Proton Ratio for Stability

An ideal balance of neutrons to protons is required for an atom to be stable.

Decay Products

The smaller nuclei and other particles resulting from a nuclear decay process.

Binding Energy

The energy required to disassemble the nucleus into its component protons and neutrons.

Decay Rate

The rate at which an unstable atom undergoes radioactive decay.

Nuclear Fusion

The process where two light atomic nuclei combine to form a heavier nucleus, releasing energy.

Half-Life

The time required for half of the radioactive nuclei in a sample to decay.

Alpha Decay

A type of radioactive decay where an alpha particle (two protons and two neutrons) is emitted.

Beta Decay

A type of radioactive decay where a neutron is converted into a proton and an electron is emitted.

Gamma Decay

A type of radioactive decay that involves the emission of gamma rays from a nucleus.

Radiation

Energy emitted from atoms in the form of particles or electromagnetic waves.

Radiochemistry

The study of chemical reactions that involve radioactive substances.

Transmutation

The process of changing one chemical element into another through nuclear reactions.

Nuclear Stability

The ability of a nucleus to maintain its structure without undergoing decay.