Unit 2 List 1 Flashcards
(23 cards)
Atoms
basic particles of the chemical elements
Molecules
a group of two or more atoms that are held together by attractive forces known as chemical bonds
Substances
matter than contains only one type of atom or molecule
Homogeneous Mixtures
a mixture where the components are evenly distributed throughout, meaning the composition is uniform and consistent no matter which part of the mixture you sample
Heterogeneous Mixtures
a mixture where the composition is not uniform throughout, meaning the different components are not evenly distributed and can be visually distinguished from one another within the mixture
Chemical Properties
a characteristic of a substance that can only be observed or measured when it undergoes a chemical change
Physical Properties
characteristics of a substance that can be observed or measured without changing the substance’s chemical identity
Isotopes
distinct nuclear species of the same chemical element
Elements
a pure substance made up of only one type of atom, meaning it cannot be broken down into simpler substances through chemical reactions.
Compounds
a chemical substance composed of many identical molecules containing atoms from more than one chemical element held together by chemical bonds
Reactants
the substances that participate in a chemical reaction, meaning they are the starting materials that undergo a chemical change to form new products.
Products
the species formed from chemical reactions. During a chemical reaction, reactants are transformed into products after passing through a high energy transition state.
Hydrogen Bonds
a specific type of molecular interaction that exhibits partial covalent character and cannot be described as a purely electrostatic force.
Covalent Bonds
a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs.
Ionic Bonds
a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, or between two atoms with sharply different electronegativities.
Cation
an ion, or charged particle, that has a positive charge, meaning it has more protons than electrons; essentially, a cation is a positively charged atom or molecule.
Anion
atoms that have gained an electron, or negatively charged subatomic particle, in order to fill their outer shell.
Periodic Table Groups
a column of elements in the periodic table of the chemical elements
Periodic Table Rows
In the periodic table, the horizontal rows are called “periods”. This means that each row across the table represents a period, and elements within the same period share similar characteristics due to having the same number of electron shells.
Valence Electrons
electrons in the outermost shell of an atom, and that can participate in the formation of a chemical bond if the outermost shell is not closed.
pH scale
measures how acidic an object is. Objects that are not very acidic are called basic. The scale has values ranging from zero (the most acidic) to 14 (the most basic)
Acids
a molecule or ion capable of either donating a proton, known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid.
Bases
substances that react with acids
