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Chapters 1-4: Chemistry of Life
(physics and chemistry) the smallest component of an element having the chemical properties of the element
any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt
the property of sticking together (as of glue and wood) or the joining of surfaces of different composition
basic building blocks of protein molecules
a negatively charged ion
an atom's dense central core, containing protons and neutrons.
the number of protons in the nucleus of an atom
(chemistry) the mass (in atomic mass units) of an isotope of an element
a solution in water
any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water
an ionic compound that resists changes in its pH
unit of heat defined as the quantity of heat required to raise the temperature of 1 gram of water by 1 degree centigrade at atmospheric pressure
an organic molecule, a functional group consisting of a carbon atom linked to a double bond to an oxygen atom C=O
A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group. -COOH
a positively charged ion
in a reversible chemical reaction, the point at which the rate of the forward reaction equals the rate of the reverse reaction.
(physics) the intermolecular force that holds together the molecules in a solid or liquid
(chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight
a chemical bond that involves sharing a pair of electrons between atoms in a molecule
a chemical bond formed when atoms share two pairs of electrons
negatively charged particle; located outside the atomic nucleus
An energy level representing the distance of an electron from the nucleus of an atom.
the ability of an atom of an element to attract electrons when the atoms is in a compound
any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
(physics) the capacity of a physical system to do work
place in an atom where an electron is most likely to be found
the property of a liquid whereby the surface becomes cooler during evaporation, owing to a loss of highly kinetic molecules to the gaseous state.
group of atoms within a molecule that interacts in predictable ways with other molecules
a form of energy that is transferred by a difference in temperature
heat of vaporization
heat absorbed by a unit mass of a material at its boiling point in order to convert the material into a gas at the same temperature
The sphere of water molecules around each dissolved ion
an organic compound containing only carbon and hydrogen
a chemical bond consisting of a hydrogen atom between two electronegative atoms (e.g., oxygen or nitrogen) with one side be a covalent bond and the other being an ionic bond
a positively charged atom of hydrogen
having a strong affinity for water
lacking affinity for water
the monovalent group -OH in such compounds as bases and some acids and alcohols
a particle that is electrically charged (positive or negative)
a chemical bond in which one atom loses an electron to form a positive ion and the other atom gains to electron to form a negative ion
a compound that consists of positive and negative ions
compounds with the same formula but different structure
one of two or more atoms with the same atomic number but with different numbers of neutrons
a unit of electrical energy equal to the work done when a current of one ampere passes through a resistance of one ohm for one second
energy of motion
the sum of the number of neutrons and protons in an atomic nucleus
that which has mass and occupies space
A chemical group consisting of a carbon bonded to three hydrogen atoms. The methyl group may be attached to a carbon or to a different atom. -CH3
a chemical formula that shows the number and kinds of atoms in a molecule, but not the arrangement of the atoms.
(physics and chemistry) the simplest structural unit of an element or compound
the molecular weight of a substance expressed in grams
concentration measured by the number of moles of solute per liter of solvent
an elementary particle with 0 charge and mass about equal to a proton
nonpolar covalent bond
a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge
a region in an atom where there is a high probability of finding electrons
the chemistry of compounds containing carbon (originally defined as the chemistry of substances produced by living organisms but now extended to substances synthesized artificially)
a value that indicated the acidity or alkalinity of a solution on a scale of 0-14, based on the proportion of H+ ions.
a functional group consisting of a phosphorus atom covalently bonded to four oxygen atoms
polar covalent bond
a covalent bond in which electrons are not shared equally
molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end
the mechanical energy that a body has by virtue of its position
the elements or compounds produced by a chemical reaction
Positively charged particles
isotope in which the nucleus decays (breaks down) over time, giving off radiation in the form of matter and energy
the elements or compounds that enter into a chemical reaction
a homogeneous mixture of two or more substances
the dissolved substance in a solution
a liquid substance capable of dissolving other substances
the heat required to raise the temperature of one gram of a substance one degree centigrade
an expanded molecular formula showing the arrangement of atoms within the molecule
a phenomenon at the surface of a liquid caused by intermolecular forces
A functional group consisting of a sulfur atom bonded to a hydrogen atom (—SH).
the average kinetic energy of the individual particles
an element that occurs at very small quantities in the body but is nonetheless important for many biological processes
The outermost energy shell of an atom, containing the valence electrons involved in the chemical reactions of that atom.
an electron in the outer shell of an atom which can combine with other atoms to form molecules
Van der Waal
weak hydrogen bonding - adhesion part of water molecule