chap 2 - flashcards - mader bio.txt

Molecules tending to raise the hydrogen ion concentration in a solution and to lower its pH numerically.

Smallest particle of an element that displays the properties of the element.

Average of atom mass units for all the isotopes of an atom.

Number of protons within the nucleus of an atom.

One or two letters that represent the name of an element�e.g.- H stands for a hydrogen atom- and Na stands for a sodium atom.

Molecules tending to lower the hydrogen ion concentration in a solution and raise the pH numerically.

Substance or group of substances that tend to resist pH changes of a solution- thus stabilizing its relative acidity and basicity.

Amount of heat energy required to raise the temperature of one gram of water 1�C.

Substance having two or more different elements united chemically in fixed ratio.

Chemical bond in which atoms share one pair of electrons.

Negative subatomic particle- moving about in an energy level around the nucleus of an atom.

Concentric energy levels in which electrons orbit.

The ability of an atom to attract electrons toward itself in a chemical bond.

Substance that cannot be broken down into substances with different properties; composed of only one type atom.

Conversion of a liquid or a solid into a gas.

A group of symbols and numbers used to express the composition of a compound.

Weak bond that arises between a slightly positive hydrogen atom of one molecule and a slightly negative atom of another molecule or between parts of the same molecule.

Hydrogen atom that has lost its electron and therefore bears a positive charge.

Type of molecule that interacts with water by dissolving in water and/or by forming hydrogen bonds with water molecules.

Type of molecule that does not interact with water because it is nonpolar.

One of two ions that results when a water molecule dissociates; it has gained an electron and therefore bears a negative charge.

Charged particle that carries a negative or positive charge.

Chemical bond in which ions are attracted to one another by opposite charges.

Atom of the same element having the same atomic number but a different mass number due to the number of neutrons.

Mass of an atom equal to the number of protons plus the number of neutrons within the nucleus.

Anything that takes up space and has mass.

Union of two or more atoms of the same element; also- the smallest part of a compound that retains the properties of the compound.

Neutral subatomic particle- located in the nucleus and assigned one atomic mass unit.

Bond in which the sharing of electrons between atoms is fairly equal.

The observation that an atom is most stable when its outer shell is complete and contains eight electrons; an exception is hydrogen which requires only two electrons in its outer shell to have a completed shell.

Measurement scale for hydrogen ion concentration.

Bond in which the sharing of electrons between atoms is unequal.

Positive subatomic particle located in the nucleus and assigned one atomic mass unit.

Ionic compound that results from a classical acid-base reaction.

Substance that is dissolved in a solvent- forming a solution.

Fluid (the solvent) that contains a dissolved solid (the solute).

Force that holds moist membranes together due to the attraction of water molecules.

Substance having an attached radioactive isotope that allows a researcher to track its whereabouts in a biological system.

Outer shell of an atom.