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rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...

activation energy

(Encyclopedia)CE5 Energy profile of an exothermic reaction: Although the total energy of the products is less than that of the reactants, the activation energy must be added to weaken or break existing bonds bef...

God

(Encyclopedia)God, divinity of the three great monotheistic religions, Judaism, Christianity, and Islam, as well as many other world religions. See also religion and articles on individual religions. There are se...

Romance languages

(Encyclopedia)CE5 Romance languages, group of languages belonging to the Italic subfamily of the Indo-European family of languages (see Italic languages). Also called Romanic, they are spoken by about 670 millio...

Emancipation Proclamation

(Encyclopedia)Emancipation Proclamation, in U.S. history, the executive order abolishing slavery in the Confederate States of America. The proclamation did not reflect Lincoln's desired solution for the slavery p...

formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...

Michael, king of Romania

(Encyclopedia)Michael, 1921–2017, king of Romania (1927–30, 1940–47). His father, Prince Carol (later Carol II), renounced his right of succession in 1925, and young Michael ascended the throne under a regenc...

mass spectrograph

(Encyclopedia)mass spectrograph, device used to separate electrically charged particles according to their masses; a form of the instrument known as a mass spectrometer is often used to measure the masses of isotop...

Herzberg, Gerhard

(Encyclopedia)Herzberg, Gerhard gĕrˈhärt hûrtsˈbûrg [key], 1904–99, Canadian physicist, b. Hamburg, Germany. He studied at Darmstadt, Göttingen, and Bristol, England, receiving a doctorate in engineering p...