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Chapter 2

Chapter 2

Atoms and Elements

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Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller …
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The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers. Leucippus and Democritus argued that all matter …
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A chemical symbol is an abbreviation used to indicate an element or an atom of an element. For example, the symbol for mercury is Hg. The same symbol is …
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In ordinary chemical reactions, the nucleus — which contains the protons and neutrons of each atom and thus identifies the element — remains …
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As early chemists discovered more elements, they realized that various elements could be grouped by their similar chemical behaviors. One such grouping …
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Atoms — and the protons, neutrons, and electrons that compose them — are extremely small. For example, a carbon atom weighs less than 2 …
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The identity of a substance is defined not only by the types of atoms or ions it contains but by the quantity of each type of atom or ion. For example, …
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A quick, automated and portable system for the separation and determination of radiostrontium in aqueous samples, using Sr-resin and multi sequential flow …
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A methodology is described to generate an isotopically pure 229Th ion beam in the 2+ and 3+ charge states. This ion beam enables one to investigate the …