Lecture 2 + Chapter 2 Flashcards
What is chemistry?
The study of interactions between atoms and molecules
What is the smallest unit of matter? Can it be subdivided into smaller substabnces
- atom, no
What are molecules?
combinations of atoms forming chemical compund
What are atoms composed of?
electrons
protons
neutrons
What is the atomic mass?
total # of protons and neutron in an atom
What are isotopes?
atoms w/ different # of neutrons
What are the elements of life?
hydrogen
- carbon
- nitrogen
- oxygen
- sodium
- magnesium
- phosphorus
How many electrons can the innermost shell hold?
2 electrons
How many electrons can the second (and possibly third) electron shell hold?
2nd holds up to 8, 3rd can hold up to eight if it is the last/outtermost shell
How many electrons can the 4th, 5th, and 6th shells hold?
Up to 18 electrons
How do Atoms form molecules?
Combining to fill their outermost shells
What is the Valence?
of missing or extra electrons in the outermost shell
How do electron hold together?
Through chemical bonds.
Valence electrons of the combining atoms form attractive forces between the atomic nuclei
What is a compound?
A molecule that contains two or more kinds of atoms
example: H2O
What are the different types of chemical bonds?
Ionic bond
Covalent
Hydrogen
What is an Ionic bond?
Attractions between ions of the opposite charge
What is an Ion?
charged atoms that have gained or lost electrons
What are Cations?
atoms that lose electrons and become positively charged ions
What are anions?
atoms that gain electrons and become negatively charged ions
What is a covalent bond?
when two atoms share one or more pairs of electrons
What is a Hydrogen bond?
when a hydrogen atom that is covalently bonded to an O or N atom is attracted to another N or O in another molecule
What is molecular mass?
The sum of atomic masses in a molecule
What is a chemical reaction?
involves the making or breaking of bonds between atoms
What does endergonic mean?
Reactions ABSORB energy
Define exergonic.
reactions RELEASE energy
What is a synthesis reaction?
occurs when atoms, ions, or molecules combine to form new, larger molecules
What is anabolism?
the synthesis of molecules in a cell
What kind of reaction is this?
A + B —> AB
Synthesis reaction
What is a Decomposition reaction?
when a molecule is split into smaller molecules, ions, or atoms
What is catabolism?
decomposition reactions in a cell
What kind of reaction is this?
AB —-> A + B
Catabolism / Decomp reaction
What is an exchange reaction?
are part synthesis and part decopmosition
What reaction is this?
NaOH + HCI —> NaCI + H2O
Exchange reaction
In what direction does reversing a chemical reaction do?
either anabolism or catabolism