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preface to fifteenth edition

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PRACTICAL LABORATORY INFORMATION 11.105<br />

TABLE 11.45<br />

Cubical Coefficients of Thermal Expansion<br />

This table lists values of , the cubical coefficient of thermal expansion, taken from “Essentials of Quantitative<br />

Analysis,” by Benedetti-Pichler, and fromvarious other sources. The value of represents the relative increases<br />

in volume for a change in temperature of 1C at temperatures in the vicinity of 25C, and is equal <strong>to</strong> 3, where<br />

is the linear coefficient of thermal expansion. Data are given for the types of glass from which volumetic<br />

apparatus is most commonly made, and also for some other materials which have been or may be used in the<br />

fabrication of apparatus employed in analytical work.<br />

Material<br />

<br />

Glasses<br />

Alkali-resistant, Corning 728<br />

1.90 10 5<br />

Gerateglas, Schott G20 1.47<br />

Kimble KG-33 (borosilicate) 0.96<br />

N-51A (“Resistant”) 1.47<br />

R-6 (soft) 2.79<br />

Pyrex, Corning 744 0.96<br />

Vitreous silica 0.15<br />

Vycor, Corning 790 0.24<br />

Metals<br />

Brass ca. 5.5<br />

Copper 5.0<br />

Gold 4.3<br />

Monel metal 4.0<br />

Platinum2.7<br />

Silver 5.7<br />

Stainless steel ca. 5.3<br />

Tantalum ca. 2.0<br />

Tungsten 1.3<br />

Plastics and other materials<br />

Hard rubber<br />

24 10 5<br />

Polyethylene 45–90<br />

Polystyrene 18–24<br />

Porcelain ca. 1.2<br />

Teflon (polytetrafluoroethylene) 16.5<br />

TABLE 11.46<br />

General Solubility Rules for Inorganic Compounds<br />

Nitrates<br />

Acetates<br />

Chlorides<br />

Sulfates<br />

Hydrogen sulfates<br />

Carbonates, phosphates,<br />

chromates, silicates<br />

Hydroxides<br />

Sulfides<br />

Sodium, potassium,<br />

ammonium<br />

Silver<br />

All nitrates are soluble.<br />

All acetates are soluble; silver acetate is moderately soluble.<br />

All chlorides are soluble except AgCl, PbCl 2 , and Hg 2 Cl 2 . PbCl 2 is soluble in<br />

hot water, slightly soluble in cold water.<br />

All sulfates are soluble except bariumand lead. Silver, mercury(I), and calciumare<br />

only slightly soluble.<br />

The hydrogen sulfates are more soluble than the sulfates.<br />

All carbonates, phosphates, chromates, and silicates are insoluble, except those<br />

of sodium, potassium, and ammonium. An exception is MgCrO 4 which is<br />

soluble.<br />

All hydroxides (except lithium, sodium, potassium, cesium, rubidium, and ammonia)<br />

are insoluble; Ba(OH) 2 is moderately soluble; Ca(OH) 2 and Sr(OH) 2<br />

are slightly soluble.<br />

All sulfides (except alkali metals, ammonium, magnesium, calcium, and barium)<br />

are insoluble. Aluminum and chromium sulfides are hydrolyzed and<br />

precipitate as hydroxides.<br />

All sodium, potassium, and ammonium salts are soluble. Exceptions:<br />

Na 4 Sb 2 O 7 ,K 2 NaCo(NO 2 ) 6 ,K 2 PtCl 6 ,(NH 4 ) 2 PtCl 6 , and (NH 4 ) 2 NaCo(NO 2 ) 6 .<br />

All silver salts are insoluble. Exceptions: AgNO 3 and AgClO 4 ;AgC 2 H 3 O 2 and<br />

Ag 2 SO 4 are moderately soluble.

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