Atoms and Isotopes test Flashcards
(24 cards)
What is radioactivity?
Radioactivity is the release of energy from the decay of nuclei, emitted by types of atoms and isotopes.
Define the term atom:
Atoms are the smallest particles of a chemical element. They make up all things that have mass.
Define the term Isotope:
Isotopes are atoms with the same number of protons and electrons but different amounts of neutrons. They are the same element as neutrons and do not affect the atom’s element.
Chemical Properties of an isotope:
They share almost the same chemical properties, but differ in mass and therefore in physical properties. There are stable isotopes, which do not emit radiation, and there are unstable isotopes, which do emit radiation.
Alpha decay
Two protons and two neutrons bound together (identical to a helium nucleus) +2
Beta Decay
A fast-moving electron from a nucleus -1
Gamma Decay
Electromagnetic radiation
What is half life?
The time it takes for half of the radiation to decay.
Electron config for the first 20 elements.
2,8,8,2
What is an ion?
An ion is an atom or group of atoms that has an electric charge. Ions with a positive charge are called cations. Ions with a negative charge are called anions.
Naming Ionic compounds
Name the metal by its elemental name.
Name the nonmetal by its elemental name and an -ide ending.
Name metals that can have different oxidation states using roman numerals to indicate positive charge. Example Fe2+ is Iron(II) …
Name polyatomic ions by their names.
Where are the metals located?
Metals are on the left of the periodic table
Where are the nonmetals located?
Non-metals are on the right.
Location of different types:
The elements in group 1 are known as the alkali metals; those in group 2 are the alkaline earth metals; those in 17 are the halogens; and those in 18 are the noble gases.
What do the groups and periods mean?
Groups: The vertical column of the periodic table that signifies the number of valence electrons in an element. Periods: The horizontal rows in the periodic table that signify the number of electron shells in an element. Families: Elements that have the same number of valence electrons and therefore similar properties.
Halogens
Highly reactive nonmetals in group 17. They have 7 valance electrons and tend to gain one electron in reactions. When combined with metals, they often form salts.
Noble gases
Elements in group 18. They are chemically inert. They have a full valence shell, making them stable and unlikely to react. Noble gasses are colourless and odourless, primarily existing as a gas.
What is radioactive decay?
Radioactive decay is the release of energy from an unstable nucleus, in the form of radiation.
Metal Properties:
Shiny, malleable, ductile, conductive of heat and electricity. High melting and boiling points, mostly solid at room temp. Often lose electrons.
Non metal properties:
Dull, brittle and poor conductors. They can exist in solids, liquids and gases at room temperature. They often gain electrons.
Alkali Metals
Highly reactive metals in group 1 of the periodic table. They have one valance electron. They are soft, shiny and have lower melting points.
Transition metals
Located in groups 3-12. They are solid and conductive metals and can form different types of ions. They often have high melting points and are commonly used in construction.
