thallium amalgam encyclopedia

Thallium (Tl)

Thallium amalgam is used in thermometers for low temperature, because it freezes at -58 °C (pure mercury freezes at -38 °C). Thallium in the environment. Thallium is not a rare element; it is 10 times more abundant than silver. The element is widely dispersed, mainly in potassium minerals such as sylvite and pollucite. Thallium minerals are ...

Thallium (Tl)

Thallium is the 81st element in the periodic table and has a symbol of Tl and atomic number of 81. It has an atomic weight of 204.380 and a mass number of 205. Thallium has eighty-one protons and one hundred twenty-four neutrons in its nucleus, and eighty-one electrons in six shells. It is located in group thirteen, period six and block p of ...

Thallium | Chemical Element, Poisonous Metal, Uses …

Thallium (Tl), chemical element, metal of main Group 13 (IIIa, or boron group) of the periodic table, poisonous and of limited commercial value. Like lead, thallium is a soft, low-melting element of low tensile …

Amalgam Definition and Uses (Chemistry)

Thallium amalgam – Thallium amalgam has a lower freezing point (−58 °C) than pure mercury (−38.8 °C). It is used in low temperature thermometers. Lead amalgam – Lead amalgam forms …

A thermodynamic study of the aqueous (sodium chloride

Section snippets Experimental. The mercury oxide electrodes were prepared as reported in an earlier work [18]. The sodium amalgam electrodes were prepared electrolytically by deposition of Na on a mercury cathode from an aqueous NaOH catholyte, and were of the flowing dilute-amalgam type [19] which ensured high accuracy and …

Emerging Thallium Pollution in China and Source Tracing by Thallium …

Thallium has only two naturally stable isotopes, with atomic masses of 203 and 205 and relative abundances of 29.5% and 70.5%, respectively. (3,4) In practice, the isotopic compositions of Tl ( 205 Tl/ 203 Tl) are best determined by reference to a standard (National Institute of Standards and Technology (NIST) 997 Tl).

Standard aqueous potentials for the thallium-amalgam …

Combining the present results with recent literature data for thallium concentration cells, the standard potentials of the thallium electrode and of the thallium/thallous-chloride electrode have been redetermined from 288.15 to 308.15 K, and can be expressed by: E Tl o V = 0.1949595 − 2.110302 × 10 −3 (T K) + 1.204957 × 10 −6 …

Thallium, Physical and Chemical Properties

Thallium is precipitated from solutions by zinc amalgam, and the relatively pure metal is obtained by an electrolytic process. Metal of the highest purity (99.9999%) can be …

Tallium | Article about Tallium by The Free Dictionary

Thallium amalgam, which solidifies at – 59°C, is used in low-temperature thermometers. Metallic thallium is used in the preparation of bearing alloys and fusible alloys, and in oxygen meters to determine oxygen concentration in water. 204 T1 is used in radioisotope devices as a source of β-emission.

Thallium | Article about thallium by The Free Dictionary

thallium. [ ′thal·ē·əm] (chemistry) A metallic element in group 13, symbol Tl, atomic number 81, atomic weight 204.383; insoluble in water, soluble in nitric and sulfuric acids, melts at 302°C, boils at 1457°C. (metallurgy) Bluish-white metal with tinlike malleability, but a little softer; used in alloys.

Thalium | Article about Thalium by The Free Dictionary

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased. Thallium . ... Thallium amalgam, which solidifies at – 59°C, is used in low-temperature thermometers. Metallic thallium is used in the preparation of bearing alloys and fusible alloys, and in oxygen meters to determine oxygen ...

Thallium and Thallium Compounds

New uses for thallium and its compounds have emerged including alloy use in bearings and contact points, amalgam use in switches and seals for use in the polar …

Amalgam

Thallium amalgam: this eutectic of this amalgam has a freezing point of −58 °C, which is lower than that of pure mercury (−38.8 °C), which allows it to be used in some low temperature thermometers. Tin amalgam: A silvery solid, it didn't have much uses besides reflective mirror coating in the 19th century on some mirrors.

Amalgam Definition and Uses (Chemistry)

Sodium amalgam – Sodium amalgam is a reducing agent used in chemistry. It's also used during high-pressure sodium lamp design to fine-tune the color and electrical properties of the lamp. Thallium amalgam – Thallium amalgam has a lower freezing point (−58 °C) than pure mercury (−38.8 °C). It is used in low temperature …

Alloy

An alloy is the combination of metal with other chemical elements (metallic or nonmetallic), forming a solution or chemical compound that retains metallic properties. Generally, a number of properties of the alloy are …

Viscosity and density of mercury-thallium amalgams

This article is cited by 3 publications. A. M. Turdukozhaeva. Temperature dependence of the dynamic viscosity of liquid mercury.

Thallus | Encyclopedia

thal·lus / ˈ [unvoicedth]aləs / • n. (pl. thal·li / ˈ [unvoicedth]alī / ) Bot. a plant body that is not differentiated into stem and leaves and lacks true roots and a vascular system. Thalli are typical of algae, fungi, lichens, and some liverworts. DERIVATIVES: thal·loid / ˈ [unvoicedth]aloid / adj. The Oxford Pocket Dictionary of ...

Standard aqueous potentials for the thallium …

Experimental The thallium amalgams required by both the thallium amalgam electrode in the cell (2) and the thallium-amalgamlthallous-chloride electrode in the cell …

Thallium Chemical Properties (25 Facts You Should Know)

Thallium (III) compounds are similar to aluminium (III). Thallium is the first of the 13 elements in the group whose compounds spontaneously degrade from an oxidation state of +3 to a state of +1. At low temperatures, thallium amalgam is used in thermometers because it freezes at -58 °C. Thallium state at room temperature

Thallium(I) chloride

Thallium (I) chloride is a colorless odorless solid. It is very toxic. It is insoluble (does not dissolve) in cold water but dissolves a little in hot water. Otherwise, it is somewhat similar to potassium chloride in being colorless and silver chloride in being insoluble in water.

Dental Amalgam

Dental amalgam has been around for hundreds of years and is still used extensively even today, despite potential concerns to both patient and clinical staff associated with mercury processing. Amalgamation constitutes the reaction with liquid mercury with any reactive metal. Mercury reacts with a range of metal powders that have been ground (using …

Thallium

thallium amalgam is used in thermometers for low temperature, because it freezes at -58 °C (pure mercury freezes at -38 °C). In addition, research activity with thallium is ongoing to develop high-temperature superconducting materials for such applications as magnetic resonance imaging, storage of magnetic energy, magnetic propulsion, and ...

Thallium Heart Scan | Encyclopedia

Thallium Heart ScanDefinitionA thallium heart scan is a diagnostic test that uses a special perfusion-scanning camera and a small amount of thallium-201, a radioactive substance, injected into the bloodstream to produce an image of the blood flow to the heart. Source for information on Thallium Heart Scan: Gale Encyclopedia of Nursing and Allied Health …

Standard potentials of the calcium amalgam electrode at …

Standard potentials for the (thallium amalgam + aqueous thallous bromide) electrode from 283.15 to 343.15 K and for the (thallium + aqueous thallous bromide) electrode from 288.15 to 308.15 K, and thermodynamic solubility product of …

Analysis of Thallium Amalgams | Analytical Chemistry …

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(PDF) Cadmium, Indium, and Thallium Production

Following co-extraction, stripping of thallium and then cadmium was found to be possible to produce solutions containing 20 to 20 g/L Cd, 2 to 5 g/L Cd, and 3 to 7 g/L Zn for thallium stripping ...

EQCM Study of the Couple Thallium(I)/Thallium Amalgam …

EQCM and voltammetric data show that thallium(I) ions, which are adsorbed in the region of the positive surface charge, most probably, in the form of the ionic pairs, are not reduced. In this potential region, thallium(I) ions are reduced directly from the solution. At more negative potentials, the previously adsorbed stable ionic pairs slowly undergo transition …

Amalgam | Encyclopedia

Amalgam. an alloy of a metal or metals —Wilkes. amalgam (əmăl´gəm), alloy [1] containing mercury [2]. The alloy may be liquid or solid, depending on the proportion of mercury, although all naturally occurring amalgams, i.e., those of gold and silver, are solid. Amalgams are widely used.

The electrical double layer on thallium amalgam electrodes

A close-packed mono- layer, of 3--A diameter spheres gives a-surface concentration of 21-- ro-10 moles/cm-2 ELECTRICAL DOUBLE LAYER ON THALLIUM AMALGAM ELECTRODES l6l and Tri in a- 40% thallium amalgam is xo-10 moles/cm2- Thus, if all the thallium were removed from. the first atomic layer, this would almost precisely account …

Presence of thallium in the environment: sources of …

Distribution of thallium in the environment. The first part of this review is focused on the distribution of thallium in the environment. This section covers the possible emission sources, aspects associated with transport of thallium-based contaminants throughout different environmental niches as well as their uptake by living organisms.