Ch 2 Flashcards
What properties of water make it essential to life?
water’s role as a solvent helps cells transport
Cohesion
water molecules are attracted to each other causing them to “stick together” bc of hydrogen bonds
Adhesion
When water molecules are attracted, or ‘‘stick’’, to other substances
How do hydrogen bond relate to the properties of
water?
gives water its high boiling point, high heat capacity, and surface tension
Hydrogen Bonds
attraction between a slightly positive hydrogen atom and slightly negative oxygen atom
Atoms
the smallest building blocks of matter
Elements
a chemical substance that cannot be broken down into other substances
Neutron
a subatomic particle found in the nucleus of an atom
help stabilize the nucleus of an atom
Subatomic
smaller than or occurring within an atom
Proton
a subatomic particle with a positive electrical charge
Electron
a tiny, negatively charged subatomic particle
Mass #
the total number of protons and neutrons in a nucleus.
Atomic #
the number of protons in the nucleus of an atom, determines its chemical properties and its place on a periodic table.
Atomic # vs. Mass #
mass number counts both protons and neutrons, atomic number only counts protons
How to calculate mass #
Add number of neutrons and number of protons together
Ionic bond
The transfer of one or more electrons to another atom
Covalent
two atoms share electrons “glueing” them together
The role of valence electrons
Form chemical bonds with other atoms
Polar molecule
uneven distribution of electrons within a molecule, one side - the other side +