N - Basic Chemistry Flashcards
Chapter 2
Anything that occupies space and has mass
Matter
Matter that has a definite shape and volume
Solid
Matter that has a definite volume; shape of the container
Liquid
Matter that has neither a definite shape nor volume
Gaseous
Matter
Changes do not alter the basic nature of a substance. Examples include changes in the state of matter like ice.
Physically
Matter
Changes alter the chemical composition of a substance
Chemically
▪ The ability to do work.
▪ It has no mass and does not take up space.
Energy
Energy doing work
Kinetic Energy
Energy is inactive of stored
Potential Energy
Energy is stored in chemical bonds of substances
Chemical Energy
Energy results from the movement of charged particles
Electrical Energy
Energy directly involved in moving matter
Mechanical Energy
The energy that travels in waves; Energy of electromagnetic spectrum
Radiant Energy
▪ Energy from conversions.
▪ Traps the chemical energy of foods in their bonds.
ATP
Adenosine Triphosphate
The fundamental units of matter
Elements
96% of the body is made from these four elements.
Oxygen
Carbon
Hydrogen
Nitrogen
Most common element and comprises 65% of the body’s mass
Oxygen
= Major component of both organic and inorganic molecules
= Essential to the oxidation of glucose and other food fuels during cellular energy (ATP) is produced
Oxygen (O)
Primary element in all organic molecules, including carbohydrates, lipids, proteins, and nucleic acids.
Carbon (C)
= Component of most organic molecules
= As an ion (charged atom), it influences the pH of body fluids
Hydrogen (H)
Component of proteins and nucleic acids (genetic material)
Nitrogen (N)
= Found as salt in bones and teeth.
= In ionic form, required for muscle contraction, neural transmission, and blood clotting.
Calcium (Ca)
= Present as salt, in combination with calcium in bones and teeth.
= Present in nucleic acids and many proteins
= Forms part of the high energy compound ATP
Phosphorus (P)
= The major intracellular cation.
= Necessary for conduction of nerve impulses and muscle contraction
Potassium (K)
Component in proteins, particularly in contractile proteins of muscle.
Sulfur (S)
= The major extracellular cation.
= Important for water balance
= Conduction of nerve impulses and muscle contraction
Sodium (Na)
The most abundant anion.
Chlorine (Cl)
= Present in bone
= Important cofactor for enzyme activity in number of metabolic reactions
Magnesium (Mg)
Needed to make functional thyroid hormones.
Iodine (I)
Component of functional hemoglobin molecule (transports oxygen within RBC) and some enzyme.
Iron (Fe)
▪ Building blocks of elements
▪ All are electrically neutral
- #P = #N
- Positive and Negative cancel each other out
Atoms
Positively charged atom found in the nucleus
Protons
Uncharged or neutral atom found in the nucleus
Neutrons
Negatively charged atom that orbits around the nucleus
Electrons
Atoms that have lost or gained electrons
Ions
▪ Portrays the atom as a miniature solar system
▪ Protons and neutrons are in the atomic nucleus
▪ Electrons are in orbitals around the nucleus
Planetary Model
Electrons are depicted by an electron cloud, a haze of
negative charge, outside the nucleus
Orbital Model
It determines an atom’s chemical behavior and bonding properties.
Electron
To identify an element, we need to know the
▪ Atomic number
▪ Atomic mass number
▪ Atomic weight
Atomic number is
Equal to the number of protons
Atomic mass number is
Sum of protons and neutrons
Atomic weight is approximately
Equal to mass number of element’s abundant isotopes
▪ Atoms that have the = same number of protons and electrons = vary in the number of neutrons = same atomic number = different atomic masses
Isotopes
▪ Heavy isotope of certain atoms
▪ Tends to be unstable
▪ Decomposes to more stable isotope
Radioisotope
▪ Process of spontaneous atomic
decay
▪ Used to tag and trace biological molecules through the body
Radioactivity
Two or more atoms of the same elements combined chemically
Molecule
Two or more atoms of different elements combined chemically
Compound
It occurs when atoms combine with or dissociate from other atoms
Chemical reactions
It is the energy relationships
involving interactions among the electrons of reacting atoms
Chemical bonds
Electrons closest to the nucleus are
most strongly
attracted to its positive charge
Distant electrons further from the nucleus are
likely to
interact with other atoms
It involves interactions only between electrons in the outermost (valence) shell
Bonding
Atoms with full valence shells
do not form bonds
Atoms are considered stable and chemically inactive (inert) when their outermost (valence) shell has
8 Electrons
Rule of Eights
▪ Form when electrons are completely transferred from one atom to another
▪ Allow atoms to achieve stability through the transfer of electrons
Ionic bonds
▪ Result from the loss or gain of electrons
▪ Tend to stay close together because opposite charges attract
Ions
Ions that have negative charge due to gain of electron(s)
Anions
Ions that have positive charge due to loss of electron(s)
Cations
▪ Atoms become stable through shared electrons
▪ Electrons are shared in pairs
Covalent bonds
Bonds that share one pair of electrons
Single covalent bonds
Bonds that share two pairs of electrons
Double covalent bonds
▪ Electrons are shared equally between the atoms of the molecule
▪ Electrically neutral as a molecule
▪ Example: carbon dioxide
Nonpolar covalent bonds
▪ Electrons are not shared equally between the atoms of the molecule
▪ Molecule has a positive and negative side or pole
▪ Example: water
Polar covalent bonds
▪ Extremely weak chemical bonds
▪ Formed when a hydrogen atom is attracted to the
negative portion, such as an oxygen or nitrogen atom,
of a polar molecule
▪ Responsible for the surface tension of water
▪ Important for forming intramolecular bonds, as in
protein structure
Hydrogen bonds
(A + B → AB)
▪ Atoms or molecules combine to form a larger, more complex molecule
▪ Energy is absorbed for bond formation
▪ Underlies all anabolic (building) activities in the body
Synthesis reaction
(AB → A + B)
▪ Molecule is broken down into smaller molecules
▪ Chemical energy is released
▪ Underlies all catabolic (destructive) activities in the
body
Decomposition reaction
AB + C → AC + B
and
AB + CD → AD + CB
▪ Involves simultaneous synthesis and decomposition
reactions as bonds are both made and broken
▪ Switch is made between molecule parts, and different
molecules are made
Exchange reaction
