ANCH P2 MOD

60問 • 1年前

Reviewer

通報

問題一覧

The phenomenon where particles of colloidal dimensions scatter visible radiation

Tyndal effect

Is a process in which a minimum number of atoms, ions, or molecules join together to give a stable solid

Nucleation

is a process in which a substance (gas, liquid, or solid) is held on the surface of a solid.

Adsorption

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

Precipitation gravimetry

he analyte is separated from other constituents of a sample by converting it to a gas of known chemical composition

Volatilization gravimetry

the analyte is separated by deposition on an electrode by an electrical current.

Electrogravimetry

is a common source of coprecipitation and is likely to cause significant contamination of precipitates with large specific surface areas.

surface adsorption

is a type of coprecipitation in which a contaminant ion replaces an ion in the lattice of a crystal.

mixed-crystal formation

type of coprecipitation in which a compound is trapped within a pocket formed during rapid crystal growth.

occlusion

it occurs when crystals lie close together during growth

mechanical entrapment

The analyte is converted to a sparingly soluble precipitate. This precipitate is then filtered, washed free of impurities, converted to a product of known composition by suitable heat treatment, and weighed.

precipitation gravimetry,

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

volatilization gravimetry

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

gravimetric titimetry

electrons are transferred from one reactant to another.

oxidation

Oxidation or reduction reaction occurring at an electrode

Half-cell Reactions

A potential developed across a boundary between electrolytes differing in concentration or chemical composition.

Liquid-junction Potential

This consists of a platinum electrode coated with platinum black to catalyze the electrode reaction and over the surface of which hydrogen at 760 mm of mercury is passed.

Standard Hydrogen Electrode (SHE)

The potential of an electrode measured relative to a standard, usually the SHE. It is a measure of the driving force of the electrode reaction and is temperature and activity dependent.

Electrode Potential E

Electrode potential measured in solutions where all reactants and products are at unit activity.

Standard Electrode Potential

The algebraic sum of the individual electrode potentials of an electrochemical cell at zero current, i.e. Ecell = Ecathode + Eanode. In practice, when current flows in a cell or a liquid junction is present (vide infra), and for certain electrode systems or reactions, the cell potential departs from the theoretical value.

Theoretical Cell Potential

A potential developed when a current I flows in an electro-chemical cell. It is a consequence of the cell resistance R and is given by the product IR. It is always subtracted from the theoretical cell potential and therefore reduces that of a galvanic cell and increases the potential required to operate an electrolysis cell.

Ohmic Drop, IR

The additional potential required to cause some electrode reactions to proceed at an appreciable rate. The result of an 'energy barrier' to the electrode reaction concerned, it is substantial for gas evolution and for electrodes made of soft metals, e.g. Hg, Pb, Sn and Zn

Activation Overpotential (Overvoltage)

The additional potential required to maintain a current flowing in a cell when the concentration of the electroactive species at the electrode surface is less than that in the bulk solution.

Concentration Overpotential or Concentration Polarization

The electrode consists of two concentric glass tubes, the inner one of which contains mercury in contact with a paste of mercury, mercury(I) chloride (calomel), and potassium chloride. This is in contact with a solution of potassium chloride in the outer tube which itself makes contact with the sample solution via a porous frit, fibre or ground-glass sleeve.

Calomel Electrode

This consists of a silver wire, coated with silver chloride and in contact with a solution of potassium chloride saturated with silver chloride. The solution is contained in a tube, the end of which is sealed with a porous plug or disc to facilitate contact with the sample solution.

Silver-silver Chloride Electrode

solates the reactants but maintains electrical contact between the two halves of the cell.

Salt bridge

It has been found that significant errors (as much as 1 or 2 pH units) may occur when the pH of samples of low ionic strength, such as lake or stream water, is measured with a glass/calomel electrode system. The prime source of such errors has been shown to be non-reproducible junction potentials, which apparently result from partial clogging of the fritted plug or porous fiber that is used to restrict the flow of liquid from the salt bridge into the analyte solution. To overcome this problem, free diffusion junctions of various types have been designed, one of which is produced commercially.

Errors in low ionic strength solutions.

A fundamental source of uncertainty for which a correction cannot be applied is the junction-potential variation resulting from differences in the composition of the standard and the unknown solution.

Variation in junction potential.

Any inaccuracies in the preparation of the buffer used for calibration or any changes in its composition during storage cause an error in subsequent pH measurements. The action of bacteria on organic buffer components is a common cause for deterioration.

Error in the pH of the standard buffer

It measure the potential of a suitable indicator electrode as a function of titrant volume. The information provided by a ---- is different from the data obtained in a direct potentiometric measurement.

Potentiometric Titration

An inert indicator electrode constructed of platinum is usually used to detect end points in this titrations. Occasionally, other inert metals, such a silver, palladium, gold, and mercury, are used instead.

Oxidation/Reduction Titrations

An ____________ electrode responds rapidly and reproducibly to changes in the concentration of an analyte ion.

Indicator Electrode

has a potential that varies in a known way with variations in the concentration of an analyte.

Indicator Electrode

a half-cell having a known electrode potential that remains constant at constant temperature and is independent of the composition of the analyte solution.

Reference Electrode

The _____________ has a potential that is accurately known, constant, and completely insensitive to the composition of the analyte solution

Reference Electrode

This technique requires only a comparison of the potential developed in a cell containing the indicator electrode in the analyte solution with its potential when immersed in one or more standard solutions of known analyte concentration.

Direct Potentiometry

Cu, Pb, Ni, Co

steels

Sn, Pb

beer and softdrinks

Transition metals

high-purity salt

Antioxidants

fuels

Riboflavin

milk, pharmaceuticals

Antibiotics

body fluids

Free sulfur

petroleum fractions

Cu, Pb, Sn, Zn

foodbuffs

Oxygen

seawater,gases

Vitamin C

fruit and vegetables

encompass a variety of electrochemical procedures having a common characteristic initial step.

Stripping methods

the analyte is deposited by reduction and then analyzed by oxidation from the small volume mercury film or drop.

ANODIC STRIPPING METHODS

the analyte is electrolyzed into a small volume of mercury by oxidation and then stripped by reduction.

CATHODIC STRIPPING METHODS

A plot of current flowing in the cell as a function of the applied potential

POLAROGRAPHY or a POLAROGRAPHIC WAVE

At small applied potentials, only a this current flows in the cell caused by the reduction of trace impurities in the sample solution and by charging of the mercury drops

RESIDUAL CURRENT

The most widely used electrode is the dropping mercury electrode (DME) and the technique involving its use is known as

POLAROGRAPHY

analogous to the behavior of a condenser

charging effect

Above the ---, at which point reduction of an electroactive species is initiated, the current increases with applied potential, until it levels off at a limiting value

DECOMPOSITION POTENTIAL

The difference between the limiting value and the residual current is known as the

DIFFUSION CURRENT

When current proportional to analyte concentration is monitored at a fixed potential.

Amperometry

Refers to a group of electroanalytical methods in which we acquire information about the analyte by measuring current in an electrochemical cell as a function of applied potential.

Voltammetry

Differs from other types of voltammetry in that the working electrode is the unique dropping mercury electrode.

Polarography

the electrode at which the analytical reaction occurs.

WORKING ELECTRODE

maintains the working electrode potential at a constant value relative to a reference electrode.

POTENTIOSTAT

PMLS

Reviewer · 87問 · 2年前

PMLS

87問 • 2年前

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ANAPHY

Reviewer · 101問 · 2年前

ANAPHY

101問 • 2年前

Reviewer

Anaphy P2

Reviewer · 100問 · 2年前

Anaphy P2

Anaphy P2 (2)

Anaphy P2 (2)

Contemporary World

Contemporary World

Pmls P2

Pmls P2

hes p3

Reviewer · 100問 · 1年前

hes p3

Anachem

Anachem

sjc l1

sjc l1

bio lab1 pic

bio lab1 pic

sjc L2

sjc L2

Biostat L3

Biostat L3

sjc L3&L4

sjc L3&L4

HIS L3

HIS L3

HIS L4

HIS L4

HIS L5

HIS L5

HIS L3

HIS L3

PSTM L3-L5

PSTM L3-L5

P1 Reviewer

P1 Reviewer

CPH P2

CPH P2

P2 Mod

P2 Mod

ANCH P2

ANCH P2

CPH

CPH

HIS

HIS

CFU ANCH P1-P3

CFU ANCH P1-P3

anch

anch

ANCH P2 Terms

ANCH P2 Terms

BIOSTAT FINALS (1)

Reviewer · 100問 · 1年前

BIOSTAT FINALS (1)

BIOSTAT FINALS (2)

BIOSTAT FINALS (2)

BIOSTAT FORMULA

BIOSTAT FORMULA

CFU CPH 1-5

CFU CPH 1-5

CFU CPH 6-16

CFU CPH 6-16

CFU CPH 17-23

CFU CPH 17-23

CFU HIS P1

CFU HIS P1

CFU HIS P2

CFU HIS P2

CFU HIS P3

CFU HIS P3

BIOSTAT FORMULA

BIOSTAT FORMULA

Mod 1-7

Mod 1-7

Mod 1

Mod 1

Mod 2

Mod 2

Mod 3

Mod 3

Mod 4

Mod 4

Mod 6

Mod 6

Mod 1-6

Mod 1-6

Mod 7

Mod 7

Mod 1

Mod 1

Mod 2

Mod 2

Mod 3

Mod 3

Mod 4

Mod 4

Mod 5

Mod 5

Mod 6

Mod 6

Mod 1-7

Mod 1-7

Mod 1

Mod 1

Mod 2

Mod 2

Mod 3

Mod 3

Mod 4

Mod 4

Mod 5

Mod 5

Mod 6

Mod 6

Mod 7

Mod 7

Mod 1

Mod 1

Mod 2

Mod 2

Mod 3

Mod 3

Mod 1

Mod 1

Mod 7

Mod 7

Mod 6

Mod 6

Mod 1

Mod 1

Mod 5

Mod 5

Mod 2

Mod 2

Mod 4

Mod 4

Mod 7

Mod 7

Mod 5

Mod 5

Mod 6

Mod 6

Mod 2

Mod 2

Mod 3

Mod 3

Mod 4

Mod 4

Mod 5

Mod 5

Lab Management

Lab Management

Biochemistry

Biochemistry

Cytogenetics

Cytogenetics

問題一覧

The phenomenon where particles of colloidal dimensions scatter visible radiation

Tyndal effect

Is a process in which a minimum number of atoms, ions, or molecules join together to give a stable solid

Nucleation

is a process in which a substance (gas, liquid, or solid) is held on the surface of a solid.

Adsorption

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

Precipitation gravimetry

he analyte is separated from other constituents of a sample by converting it to a gas of known chemical composition

Volatilization gravimetry

the analyte is separated by deposition on an electrode by an electrical current.

Electrogravimetry

is a common source of coprecipitation and is likely to cause significant contamination of precipitates with large specific surface areas.

surface adsorption

is a type of coprecipitation in which a contaminant ion replaces an ion in the lattice of a crystal.

mixed-crystal formation

type of coprecipitation in which a compound is trapped within a pocket formed during rapid crystal growth.

occlusion

it occurs when crystals lie close together during growth

mechanical entrapment

precipitation gravimetry,

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

volatilization gravimetry

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

gravimetric titimetry

electrons are transferred from one reactant to another.

oxidation

Oxidation or reduction reaction occurring at an electrode

Half-cell Reactions

A potential developed across a boundary between electrolytes differing in concentration or chemical composition.

Liquid-junction Potential

This consists of a platinum electrode coated with platinum black to catalyze the electrode reaction and over the surface of which hydrogen at 760 mm of mercury is passed.

Standard Hydrogen Electrode (SHE)

The potential of an electrode measured relative to a standard, usually the SHE. It is a measure of the driving force of the electrode reaction and is temperature and activity dependent.

Electrode Potential E

Electrode potential measured in solutions where all reactants and products are at unit activity.

Standard Electrode Potential

Theoretical Cell Potential

Ohmic Drop, IR

Activation Overpotential (Overvoltage)

The additional potential required to maintain a current flowing in a cell when the concentration of the electroactive species at the electrode surface is less than that in the bulk solution.

Concentration Overpotential or Concentration Polarization

Calomel Electrode

Silver-silver Chloride Electrode

solates the reactants but maintains electrical contact between the two halves of the cell.

Salt bridge

Errors in low ionic strength solutions.

Variation in junction potential.

Error in the pH of the standard buffer

Potentiometric Titration

Oxidation/Reduction Titrations

An ____________ electrode responds rapidly and reproducibly to changes in the concentration of an analyte ion.

Indicator Electrode

has a potential that varies in a known way with variations in the concentration of an analyte.

Indicator Electrode

a half-cell having a known electrode potential that remains constant at constant temperature and is independent of the composition of the analyte solution.

Reference Electrode

The _____________ has a potential that is accurately known, constant, and completely insensitive to the composition of the analyte solution

Reference Electrode

Direct Potentiometry

Cu, Pb, Ni, Co

steels

Sn, Pb

beer and softdrinks

Transition metals

high-purity salt

Antioxidants

fuels

Riboflavin

milk, pharmaceuticals

Antibiotics

body fluids

Free sulfur

petroleum fractions

Cu, Pb, Sn, Zn

foodbuffs

Oxygen

seawater,gases

Vitamin C

fruit and vegetables

encompass a variety of electrochemical procedures having a common characteristic initial step.

Stripping methods

the analyte is deposited by reduction and then analyzed by oxidation from the small volume mercury film or drop.

ANODIC STRIPPING METHODS

the analyte is electrolyzed into a small volume of mercury by oxidation and then stripped by reduction.

CATHODIC STRIPPING METHODS

A plot of current flowing in the cell as a function of the applied potential

POLAROGRAPHY or a POLAROGRAPHIC WAVE

At small applied potentials, only a this current flows in the cell caused by the reduction of trace impurities in the sample solution and by charging of the mercury drops

RESIDUAL CURRENT

The most widely used electrode is the dropping mercury electrode (DME) and the technique involving its use is known as

POLAROGRAPHY

analogous to the behavior of a condenser

charging effect

Above the ---, at which point reduction of an electroactive species is initiated, the current increases with applied potential, until it levels off at a limiting value

DECOMPOSITION POTENTIAL

The difference between the limiting value and the residual current is known as the

DIFFUSION CURRENT

When current proportional to analyte concentration is monitored at a fixed potential.

Amperometry

Refers to a group of electroanalytical methods in which we acquire information about the analyte by measuring current in an electrochemical cell as a function of applied potential.

Voltammetry

Differs from other types of voltammetry in that the working electrode is the unique dropping mercury electrode.

Polarography

the electrode at which the analytical reaction occurs.

WORKING ELECTRODE

maintains the working electrode potential at a constant value relative to a reference electrode.

POTENTIOSTAT