electropositiveadj.

Brit.

/ᵻˌlɛktrəʊˈpɒzᵻtɪv/, U.S.

/əˌlɛktrəˈpɑzədɪv/,

/iˌlɛktrəˈpɑzədɪv/

Origin: Formed within English, by compounding; modelled on a French lexical item. Etymons: electro- comb. form, positive adj.

Etymology: < electro- comb. form + positive adj., after French électropositif (1811 in a translation of Berzelius, in Journal de physique, de chimie et d'histoire naturelle 73 257). Compare electronegative adj.

1. Chemistry. Of a substance, ion, etc.: attracted to or reacting at the negative electrode (cathode) in electrolysis. Hence, of an element or group: tending to lose electrons and form positive ions in chemical reactions. Contrasted with electronegative adj. 1. Cf. the note at electronegativity n.

ΚΠ

1813 tr. J. J. Berzelius in Ann. Philos. 2 453 If..an acid or electro-negative oxide is neutralized by a quantity of base or electro-positive oxide.

1834 M. Faraday in Philos. Trans. (Royal Soc.) 124 79 Substances are frequently spoken of as being electro-negative, or electro-positive, according as they go under the supposed influence of a direct attraction to the positive or negative pole.

1850 C. G. B. Daubeny Introd. Atomic Theory (ed. 2) vii. 205 Chlorine, an electro-negative body, takes the place of hydrogen, an electro-positive one.

1883 Chambers's Jrnl. 1 Dec. 765/1 Tin is..electro-positive to iron.

1924 A. J. Allmand & H. J. T. Ellingham Princ. Appl. Electrochem. (ed. 2) xxi. 497 Turning to electrochemical methods, we are often debarred from depositing from aqueous solutions, as strongly electropositive metals decompose water.

1969 Proc. National Acad. Sci. U.S.A. 62 662 The more electropositive groups (CH₃) tend to occupy basal positions, while the more electronegative groups (OCH₃) tend to occupy apical positions.

1988 J. D. Barrow & F. J. Tipler Anthropic Cosmol. Princ. (rev. ed.) viii. 543 Hydrogen is the most electropositive of all elements, and it donates electrons to form strong bonds with the electronegative halogens.

2007 Jrnl. Materials Processing Technol. 182 382/2 Due to the high electropositive nature of transition-metal atoms, transition-metal alkoxides are reactive.

2. Electrically positive, having a positive charge.

ΚΠ

1862 R. H. Patterson Ess. Hist. & Art 13 The electro-positive and electro-negative rays, of which Heat and Actinism are the representatives.

1922 New Phytologist 21 125 These protoplasts..refuse passage to complex ions with an electropositive charge so long as they retain their living semi-permeable membranes.

1942 Amer. Naturalist 76 593 Churney and Klein..have demonstrated, in the salivary gland nuclei of Sciara, that the chromosomes are electro-negative while the nucleus as a whole is electro-positive.

2006 European Jrnl. Pharmaceut. Sci. 29 378/2 Both lactose..and salbutamol sulphate..acquired a net electronegative charge, whereas ipratropium bromide..acquired a net electropositive charge following agitation in the film coated vessels.

Derivatives

eˌlectroˈpositively adv. as an electropositive species or group; in an electropositive manner.

ΚΠ

1851 H. Medlock tr. F. Schoedler Bk. Nature i. 232 In the following electrical series, the elements are so arranged that each substance deports itself electro-negatively towards those which follow, and electro-positively to those which precede it.

1874 Manufacturer & Builder Oct. 230/2 We know positively that our earth has a constant electro-negative charge, and have reason to suspect that the sun is electro-positively charged.

1960 Biometrics 16 279 The interior of the fibre becomes electropositively charged in relation to the exterior.

2006 Plant Physiol. & Biochem. 44 538/1 Mapping of electrostatic potentials on the molecular surface..revealed a predominantly electropositively charged surface.

This entry has been updated (OED Third Edition, June 2008; most recently modified version published online March 2022).

单词	electropositive
释义	electropositiveadj. Brit. /ᵻˌlɛktrəʊˈpɒzᵻtɪv/, U.S. /əˌlɛktrəˈpɑzədɪv/, /iˌlɛktrəˈpɑzədɪv/ Origin: Formed within English, by compounding; modelled on a French lexical item. Etymons: electro- comb. form, positive adj. Etymology: < electro- comb. form + positive adj., after French électropositif (1811 in a translation of Berzelius, in Journal de physique, de chimie et d'histoire naturelle 73 257). Compare electronegative adj. 1. Chemistry. Of a substance, ion, etc.: attracted to or reacting at the negative electrode (cathode) in electrolysis. Hence, of an element or group: tending to lose electrons and form positive ions in chemical reactions. Contrasted with electronegative adj. 1. Cf. the note at electronegativity n. ΚΠ 1813 tr. J. J. Berzelius in Ann. Philos. 2 453 If..an acid or electro-negative oxide is neutralized by a quantity of base or electro-positive oxide. 1834 M. Faraday in Philos. Trans. (Royal Soc.) 124 79 Substances are frequently spoken of as being electro-negative, or electro-positive, according as they go under the supposed influence of a direct attraction to the positive or negative pole. 1850 C. G. B. Daubeny Introd. Atomic Theory (ed. 2) vii. 205 Chlorine, an electro-negative body, takes the place of hydrogen, an electro-positive one. 1883 Chambers's Jrnl. 1 Dec. 765/1 Tin is..electro-positive to iron. 1924 A. J. Allmand & H. J. T. Ellingham Princ. Appl. Electrochem. (ed. 2) xxi. 497 Turning to electrochemical methods, we are often debarred from depositing from aqueous solutions, as strongly electropositive metals decompose water. 1969 Proc. National Acad. Sci. U.S.A. 62 662 The more electropositive groups (CH₃) tend to occupy basal positions, while the more electronegative groups (OCH₃) tend to occupy apical positions. 1988 J. D. Barrow & F. J. Tipler Anthropic Cosmol. Princ. (rev. ed.) viii. 543 Hydrogen is the most electropositive of all elements, and it donates electrons to form strong bonds with the electronegative halogens. 2007 Jrnl. Materials Processing Technol. 182 382/2 Due to the high electropositive nature of transition-metal atoms, transition-metal alkoxides are reactive. 2. Electrically positive, having a positive charge. ΚΠ 1862 R. H. Patterson Ess. Hist. & Art 13 The electro-positive and electro-negative rays, of which Heat and Actinism are the representatives. 1922 New Phytologist 21 125 These protoplasts..refuse passage to complex ions with an electropositive charge so long as they retain their living semi-permeable membranes. 1942 Amer. Naturalist 76 593 Churney and Klein..have demonstrated, in the salivary gland nuclei of Sciara, that the chromosomes are electro-negative while the nucleus as a whole is electro-positive. 2006 European Jrnl. Pharmaceut. Sci. 29 378/2 Both lactose..and salbutamol sulphate..acquired a net electronegative charge, whereas ipratropium bromide..acquired a net electropositive charge following agitation in the film coated vessels. Derivatives eˌlectroˈpositively adv. as an electropositive species or group; in an electropositive manner. ΚΠ 1851 H. Medlock tr. F. Schoedler Bk. Nature i. 232 In the following electrical series, the elements are so arranged that each substance deports itself electro-negatively towards those which follow, and electro-positively to those which precede it. 1874 Manufacturer & Builder Oct. 230/2 We know positively that our earth has a constant electro-negative charge, and have reason to suspect that the sun is electro-positively charged. 1960 Biometrics 16 279 The interior of the fibre becomes electropositively charged in relation to the exterior. 2006 Plant Physiol. & Biochem. 44 538/1 Mapping of electrostatic potentials on the molecular surface..revealed a predominantly electropositively charged surface. This entry has been updated (OED Third Edition, June 2008; most recently modified version published online March 2022). < adj.1813
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