Ch. 18 Key Terms - Chemistry | OpenStax

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Key Terms

acid anhydride: compound that reacts with water to form an acid or acidic solution

alkaline earth metal: any of the metals (beryllium, magnesium, calcium, strontium, barium, and radium) occupying group 2 of the periodic table; they are reactive, divalent metals that form basic oxides

allotropes: two or more forms of the same element, in the same physical state, with different chemical structures

amorphous: solid material such as a glass that does not have a regular repeating component to its three-dimensional structure; a solid but not a crystal

base anhydride: metal oxide that behaves as a base towards acids

bicarbonate anion: salt of the hydrogen carbonate ion, ${HCO}_{3}^{-}$

bismuth: heaviest member of group 15; a less reactive metal than other representative metals

borate: compound containing boron-oxygen bonds, typically with clusters or chains as a part of the chemical structure

carbonate: salt of the anion ${CO}_{3}^{2-};$ often formed by the reaction of carbon dioxide with bases

chemical reduction: method of preparing a representative metal using a reducing agent

chlor-alkali process: electrolysis process for the synthesis of chlorine and sodium hydroxide

disproportionation reaction: chemical reaction where a single reactant is simultaneously reduced and oxidized; it is both the reducing agent and the oxidizing agent

Downs cell: electrochemical cell used for the commercial preparation of metallic sodium (and chlorine) from molten sodium chloride

Frasch process: important in the mining of free sulfur from enormous underground deposits

Haber process: main industrial process used to produce ammonia from nitrogen and hydrogen; involves the use of an iron catalyst and elevated temperatures and pressures

halide: compound containing an anion of a group 17 element in the 1− oxidation state (fluoride, F⁻; chloride, Cl⁻; bromide, Br⁻; and iodide, I⁻)

Hall–Héroult cell: electrolysis apparatus used to isolate pure aluminum metal from a solution of alumina in molten cryolite

hydrogen carbonate: salt of carbonic acid, H₂CO₃ (containing the anion ${HCO}_{3}^{−})$ in which one hydrogen atom has been replaced; an acid carbonate; also known as bicarbonate ion

hydrogen halide: binary compound formed between hydrogen and the halogens: HF, HCl, HBr, and HI

hydrogen sulfate: ${HSO}_{4}^{-}$ ion

hydrogen sulfite: ${HSO}_{3}^{-}$ ion

hydrogenation: addition of hydrogen (H₂) to reduce a compound

hydroxide: compound of a metal with the hydroxide ion OH⁻ or the group −OH

interhalogen: compound formed from two or more different halogens

metal (representative): atoms of the metallic elements of groups 1, 2, 12, 13, 14, 15, and 16, which form ionic compounds by losing electrons from their outer s or p orbitals

metalloid: element that has properties that are between those of metals and nonmetals; these elements are typically semiconductors

nitrate: ${NO}_{3}^{-}$ ion; salt of nitric acid

nitrogen fixation: formation of nitrogen compounds from molecular nitrogen

Ostwald process: industrial process used to convert ammonia into nitric acid

oxide: binary compound of oxygen with another element or group, typically containing O²⁻ ions or the group –O– or =O

ozone: allotrope of oxygen; O₃

passivation: metals with a protective nonreactive film of oxide or other compound that creates a barrier for chemical reactions; physical or chemical removal of the passivating film allows the metals to demonstrate their expected chemical reactivity

peroxide: molecule containing two oxygen atoms bonded together or as the anion, $O_{2}^{2−}$

photosynthesis: process whereby light energy promotes the reaction of water and carbon dioxide to form carbohydrates and oxygen; this allows photosynthetic organisms to store energy

Pidgeon process: chemical reduction process used to produce magnesium through the thermal reaction of magnesium oxide with silicon

polymorph: variation in crystalline structure that results in different physical properties for the resulting compound

representative element: element where the s and p orbitals are filling

representative metal: metal among the representative elements

silicate: compound containing silicon-oxygen bonds, with silicate tetrahedra connected in rings, sheets, or three-dimensional networks, depending on the other elements involved in the formation of the compounds

sulfate: ${SO}_{4}^{2−}$ ion

sulfite: ${SO}_{3}^{2−}$ ion

superoxide: oxide containing the anion $O_{2}^{-}$

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Authors: Paul Flowers, William R. Robinson, PhD, Richard Langley, Klaus Theopold
Publisher/website: OpenStax
Book title: Chemistry
Publication date: Mar 11, 2015
Location: Houston, Texas
Book URL: https://openstax.org/books/chemistry/pages/1-introduction
Section URL: https://openstax.org/books/chemistry/pages/18-key-terms

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