Gravimetric Analysis

Question 1

Are quantitative methods based on determining the mass of a pure compound to which the analyte is chemically related

Answer 1

Gravimetric Methods

Question 2

The analyte is separated from a solution of the sample as a precipitate and is converted to a compound of known composition that can be weighed.

Answer 2

Precipitation Gravimetry

Question 3

The analyte is separated from the other constituents of a sample by converting it to a gas of known chemical composition. The mass of the gas serves as a measure of the analyte concentration.

Answer 3

Volatilization Gravimetry

Question 4

The analyte is separated by deposition on an electrode by an electrical current and the mass of this product provides a measure of the analyte concentration.

Answer 4

Electrogravimetry

Question 5

The mass of a reagent of known concentration required to react completely with the analyte provides the information needed to determine the analyte concentration.

Answer 5

Gravimetric Titrimetry

Question 6

Uses a mass spectrometer to separate gaseous ions formed from the elements making up a sample of matter. The concentration of the ions is determined by measuring the electrical current when they fall on the surface of the detector.

Answer 6

Atomic mass spectometry

Question 7

Consists of solid particles with diameters that are less than 10^-4 cm.

Answer 7

Colloids

Question 8

Contain tiny particles invisible to the naked eye (10^-7 to 10^-4 cm in diameter)

Answer 8

Colloidal Suspension

Question 9

Describes a solution in which particles with dimensions on the order of a tenth of a millimeter or greater are temporarily dispersed in the liquid phase.

Answer 9

Crystalline solution

Question 10

An unstable solution that contains a higher solute concentration than a saturated solution.

Answer 10

Supersaturated solution

Question 11

The process by which a minimum number of atoms, ions, or molecules join together to give a stable solid.

Answer 11

Nucleation

Question 12

A process by which a substance is held on the surface of a solid.

Answer 12

Adsorption

Question 13

The retention of a substance within the pores of a solid.

Answer 13

Absorption

Question 14

The process by which a coagulated colloid reverts to its original dispersed state.

Answer 14

Peptization

Question 15

A process in which a precipitate is heated in the solution from which it was formed (the mother liquor) and allowed to stand in contact with the solution.

Answer 15

Digestion

Question 16

A process in which normally soluble compounds are carried out of solution by a precipitate.

Answer 16

Coprecipitation

Question 17

Common and can cause significant contamination of precipitates with large specific surface areas (i.e., coagulated colloids).

Answer 17

Surface adsorption

Question 18

The filtered solid is redissolved and reprecipitated to reduce the contaminant concentration.

Answer 18

Reprecipitation

Question 19

Defined as the surface area per unit mass of solid and usually has the units of square centimeters per gram.

Answer 19

Specific surface area

Question 20

A contaminant replaces an ion in the lattice of a crystal.

Answer 20

Mixed crystal formation

Question 21

A compound is trapped within a pocket formed during rapid crystal growth.

Answer 21

Occlusion

Question 22

Crystals grow together and trap a portion of the solution in a tiny pocket

Answer 22

Mechanical entrapment

Question 23

A process in which a precipitate is formed by slow generation of a precipitating reagent homogeneously throughout a solution.

Answer 23

Homogeneous precipitation

Question 24

A process of recording thermal decomposition curves.

Answer 24

Thermogravimetric analysis

Question 25

The mass versus temperature curves.

Answer 25

Thermograms

Question 26

The combined constant factors in a gravimetric calculation.

Answer 26

Gravimetric factor

Question 27

Lightly soluble nonionic products.

Answer 27

Coordination compounds

Question 28

Organic reagents that yield sparingly soluble coordination compounds typically contain at least two functional groups that are each capable of bonding with a cation by donating a pair of electrons.

Answer 28

Chelating agents

Question 29

The products of the reaction involving chelating agents

Answer 29

Chelates