Term
Define "states of matter" |
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Definition
The physical forms in which matter exists: solid, liquid, and gas.
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Term
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Definition
The weight of an element is defined as the weighted average of the masses of all of its natural occurring isotopes.
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Term
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Definition
The weight of a molecule is the total mass of the individual atoms.
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Term
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Definition
One mole represents a definite number of objects, substances, or particles. (For example, a mole of atoms, a mole of ions, a mole of molecules, and even,
theoretically, a mole of elephants.)
A mole is defined as the quantity of a pure substance that contains 6.02 x 1023
units (atoms, ions, molecules, or elephants) of that substance.
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Term
Define gram atomic weight |
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Definition
The mass of a mole of atoms is called the gram atomic weight (GAW).
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Term
Define gram molecular weight |
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Definition
The mass of a mole of molecules is called the molar mass or gram molecular weight (GMW).
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Term
LIST the components of an atom, relative sizes, and charges.
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Definition
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Term
STATE the criterion used to classify an atom chemically
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Definition
An atom is classified chemically by the number of protons in its nucleus (atomic number)
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Term
DEFINE the following subdivisions of the periodic table:
– Periods
– Groups
– Classes
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Term
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Definition
The term valence (of an atom) is defined as the number of electrons an element gains or loses, or the number of pairs of electrons it shares when it interacts with other elements.
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Term
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Definition
An ionic bond is formed when one or more electrons is wholly transferred from one element to another, and the elements are held together by the force of attraction due to the opposing charges. |
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Term
Define Van der Waals forces |
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Definition
The temporary dipole induces a similar temporary dipole on a nearby atom, ion, or molecule. Every instant, billions of these temporary dipoles form, break apart, and reform to act as a weak electrostatic force of attraction known as Van der Waals forces
.
These forces occur between the molecules of nonpolar covalent substances
These forces are generally believed to be caused by a temporary dipole, or unequal charge distribution, as electrons constantly move about in an atom, ion, or molecule.
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Term
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Definition
A covalent bond is formed when one or more electrons from an atom pair off with one or more electrons from another atom and form overlapping electron shells in which both atoms share the paired electrons.
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Term
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Definition
In the metallic bond, an atom achieves a more stable configuration by sharing the electrons in its outer shell with many other atoms.
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Term
DESCRIBE the physical arrangement and bonding of a polar molecule.
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Definition
When the shared pair of electrons is
NOT
shared equally, one end of the bond is positive, and the other end is negative.
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Term
DESCRIBE the three basic laws of chemical reactions.
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Definition
The Law of Conservation of Mass - total mass of the products equals the total mass of the reactants
The Law of Definite Proportions -
no matter how a given chemical compound is prepared, it always contains the same elements in the same proportions by mass.
The Law of Multiple Proportions -
if two elements combine to form more than one compound, the masses of one of the elements combining with a fixed mass of the other are in a simple ratio to one another
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Term
STATE how elements combine to form chemical compounds.
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Definition
The Laws of Definite Proportions and Multiple Proportions and the related portions of atomic theory form the bases for most quantitative calculations involving chemical reactions.
Regardless of the type of bond (ionic, covalent, or metallic), specific amounts of one element will react with specific amounts of the element(s) with which it
is combined.
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Term
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Definition
If two substances are placed together in a container, in any ratio, the result is a mixture.
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Definition
The solvent is the material that dissolves the other substance(s).
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Term
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Definition
Solubility is defined as the maximum amount of a substance that can dissolve in a given amount of solvent at a specific temperature.
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Definition
The substances that dissolve in the solution are called solutes
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Term
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Definition
A homogeneous mixture of two or more substances is called a solution
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Term
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Definition
Equilibrium is the point at which the rates of the forward and reverse reactions are exactly equal for a chemical reaction if the conditions of reaction are constant.
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Term
STATE Le Chateleir’s principle.
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Definition
Le Chatelier's Principle states that if a stress (for example, heat, pressure, concentration of one reactant) is applied to an equilibrium, the system will
adjust, if possible, to minimize the effect of the stress.
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Term
Define Parts per Million (ppm) |
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Definition
The term ppm is defined as the concentration of a solution in units of one part of solute to one million parts solvent.
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Term
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Definition
Density is the measure of the mass per unit volume of a material
(density = mass/volume).
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Term
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Definition
Molarity is defined as moles of solute per liter of solution.
Molarity (M) = moles of solute (n)/liters of solution (V)
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Definition
Normality (N) is defined as the number of equivalents of solute dissolved in one liter of solution.
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Term
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Definition
Acids are substances that dissociate in water to produce hydrogen (H+).
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Term
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Definition
When an acid reacts with a base, forms two products: water and a salt.
A salt is an ionic compound composed of positive ions and negative ions
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Term
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Definition
The
pOH of a solution is defined as the negative logarithm of the hydroxyl concentration, represented as [OH-] in moles/liter.
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Term
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Definition
Certain soluble salts (principally sodium, potassium, magnesium, and calcium) that have the property of combining with acids to form neutral salts are called
alkalies.
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Definition
Bases are substances that produce hydroxide ions (OH
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) in water solutions.
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Term
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Definition
ph is defined as the negative logarithm of the hydrogen concentration, represented as [H +] in moles/liter.
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