Chapters 11 Flashcards
Analytical chemistry
The branch of modern chemistry that deals with the separation, purification, identification and quantification of chemical substances.
Anion
A negatively charged ion.
Cation
A positively charged ion.
Atom
The basic chemical unit of an element that retains the chemical properties of the element.
Atomic Number
The number of protons in the nucleus of an atom.
Atomic Mass (weight)
The mass of an atom that is expressed in the standard unit of atomic mass units (amu): approximately equal to the number of protons and neutrons in the atom.
Chemical Analysis
The process of determining the composition of a substance
Chemical Property
The property of a substance characterized by a chemical reaction and causing a change in the starting substance.
Chromatography
The process of separating the components of a mixture that relies on the differential affinities of the various components with some medium, such as a solid, gas or
liquid.
Classical Analysis
Direct chemical methods for analysis of a substance.
Combustion Analysis
The method to determine the composition of a substance by reacting it with oxygen in a combustion reaction and quantitatively characterizing the products formed.
Primarily used for carbon and hydrogen analysis of organic compounds.
Detection Limit
The smallest amount of a substance that can be distinguished with certainty from
the background or the absence of the substance.
Concentration
The amount of solute dissolved in a specific quantity of solvent, usually given in moles of solute in one liter of solution (molarity)
Confirmatory Test (chemical)
An analytical procedure used with a high degree of certainty to identify a substances or the components of a mixture
Element
A substance that cannot be separated into simpler substances by chemical means, consisting of atoms with the same number of protons.
Conservation of Mass (Law of)
The physical law that states that matter cannot be created or destroyed
Empirical Formula
The formula of a substance that shows the relative proportions of the elements present but not necessarily the actual molecular composition of the substance.
Destructive Analysis
A chemical process where the sample is destroyed during the analytical procedure
Extrinsic Properties
Physical properties that depend upon the amount of substance present, such as heat and mass
Constant Composition (Law of)
The principle that states that a pure compound always containsthe same elements in exactly the same relative proportions.
Density
The mass of a substance per unit volume.
Electron
The small, stable subatomic particle carrying a negative charge equal and opposite to the positive charge on the proton.
Gas
A substance that moves freely to fill all available space, without a definite shape or volume.
Heterogeneous Mixture
A mixture that is composed on two or more components that does not result in a uniform composition, appearance or properties.
Homogeneous Mixture
A mixture that is composed on two or more components that results in a uniform composition, appearance or properties.
Immunoassay
A chemical analysis that relies upon the binding of an antibody with its antigen to identify and quantify the substance.
Proton
A subatomic particle with about the same mass as a neutron but with a positive electrical charge equal and opposite to that of the electron.
Product
A substance that is the result of a chemical reaction.
Reactant
A substance that reacts during the course of a chemical reaction and is changed into a different substance.
Physical Properties
A property used to characterize a substance, such as boiling point and density, and that does not require a chemical reaction to define.
Molecular Weight
The mass of a molecule that is expressed in the standard unit of atomic mass units (amu). Determined by the sum of the atomic masses of all of the atoms that make up the
molecule.
Gravimetric Analysis
A chemical analytical technique that measures the product of a known chemical reaction in order determining the composition of the starting material.
Liquid
A substance that is without a definite shape but has a fixed volume.
Intrinsic Properties
Physical properties that do not depend upon the amount of substance present, such as density and chemical composition.
Neutron
A subatomic particle with about the same mass as a proton but without an electrical charge.
Ion
A charged particle or molecule.
Molarity
The number of moles of a solute in one liter of solution.
Percent Composition
The chemical analysis that provides the percentage by mass of each element in the compound.
Instrumental Analysis
The area of analytical chemistry that performs the analysis using scientific instruments such as spectrophotometers or spectrometers.
Isotope
Atoms with the same number of protons but different numbers of neutrons.
Mobile Phase
In chromatography, the component that moves the solute past a fixed medium.
Isomers
Chemical compounds with the same molecular formula but with different arrangements of the atoms and properties.
Quantitative Analysis
The measurement of the amounts of the components in a substance.
Qualitative Analysis
The determination of the identities of the components in a substance.
Solid
A substance that has both a definite shape and a fixed volume
Solute
The substance dissolved in a solvent.
Solvent
The liquid that is used to dissolve a solute.
Solubility
The degree to which a solute (solid) will dissolve in a solvent.
Stationary Phase
In chromatography, the component that remains fixed (does not move) during the separation.
Stoichiometry
The relative quantities of reactants and products in chemical reactions.
Retention Factor (Rf)
A measure of the degree of interaction of a substance in chromatography with the stationary phase. Determined by dividing the distance the substance traveled by the
distance the mobile phase traveled during a period of time.