Biology: The Chemical Basis of Life Flashcards
Element
Pure substance that can not be broken down into another substance
Matter
Everything that takes up space and has mass
Compound
Substance containing more than one chemically combined
Atom
Smallest particle of an element
Proton
Positively charged subatomic particle
Electron
Negatively charged subatomic particle
Neutron
Neutrally charged subatomic particle
Nucleus
Center part of an atom that contains protons and neutrons
Atomic number
Equal to number of protons in an atom
Atomic mass
Equal to the sum of protons and neutrons in one atom
Isotope
Same number of protons, different of neutrons
Ionic bond
Form when atom gains or loses electron to form ions, oppositely charged ions attract and form a chemical bond
Ion
Atom that is charged from gaining or losing electron
Covalent bond
Atoms that share electrons, each atom is going to share one electron in the electron pair
Molecule
Two or more atoms joined together chemically
Chemical reactions
Breaking of olds and new bonds for new substance
Valence electrons
Electrons on the outside ring
Polar molecule
Electrons aren’t being shared
Hydrogen bond
a slightly positive hydrogen atom in one molecule is attracted to a slightly negative atom in a different molecule
Thermal energy
Amount of energy associated with random movements of atoms and molecules
Cohesion
Sticking together
Adhesion
Process of attachment of a substance to the surface of another substance
Surface tension
the force that causes the molecules on the surface of a liquid to be pushed together and form a layer
Solution
Mixture of two or more substances
