Download Chemistry Terms: Atoms, Elements, Compounds, and Chemical Bonds and more Quizzes Biology in PDF only on Docsity!
Matter
Matter is a general term for the substance of which all physical objects are made. Anything that takes up space and has mass TERM 2
Element
DEFINITION 2 a substance that can't be broken down to other substances by chemical reactions 92 elements TERM 3
Compound
DEFINITION 3 a substance consisting of two or more different elements combined in a fixed ratio TERM 4
Trace elements
DEFINITION 4 those required by an organisms in minute quantities TERM 5
atom
DEFINITION 5 The atom is a basic unit of matter that consists of a dense, central nucleus surrounded by a cloud of negatively charged electrons.
Dalton
The unified atomic mass unit (symbol: u), also called the dalton (symbol: Da), is a unit used for indicating mass on an atomic or molecular scale. TERM 7
Atomic Number
DEFINITION 7 In chemistry and physics, the atomic number (also known as the proton number) is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. TERM 8
Mass Number
DEFINITION 8 the sum of the proton plus neutrons in the nucleus of an atom TERM 9
Isotopes
DEFINITION 9 Isotopes are different types of atoms (nuclides) of the same chemical element, each having a different number of neutrons. Although they have slightly different masses, they behave identically in chemical reactions TERM 10
Radioactive Isotope
DEFINITION 10 one in which the nucleus decays spontaneously, giving off particles and energy
Covalent Bond
A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, and other covalent bonds. TERM 17
Molecule
DEFINITION 17 A molecule is defined as an electrically neutral group of at least two atoms in a definite arrangement held together by very strong (covalent) chemical bonds. TERM 18
Single Bond
DEFINITION 18 pair of shared electron TERM 19
Electronegativity
DEFINITION 19 Electronegativity, symbol (the Greek letter chi), is a chemical property that describes the ability of an atom (or, more rarely, a functional group) to attract electrons (or electron density) towards itself. TERM 20
Nonpolar Covalent Bond
DEFINITION 20 a bond in which electrons are shared equally
Polar Covalent Bond
In chemistry, polarity refers to a separation of electric charge leading to a molecule having an electric dipole. TERM 22
Ion
DEFINITION 22 An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. TERM 23
Ionic Bond
DEFINITION 23 An ionic bond is a type of chemical bond that involves a metal and a nonmetal ion (or polyatomic ions such as ammonium) through electrostatic attraction. TERM 24
Hydrogen Bond
DEFINITION 24 A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen or fluorine (thus the name "hydrogen bond," which should not be confused with a covalent bond to hydrogen). TERM 25
Van der Waals
DEFINITION 25 In chemistry, van der Waals strain is strain resulting from van der Waals repulsion when two substituents in a molecule approach each other with a distance less than the sum of their van der Waals radii.
