Cal-red

Calcium is determined in serum by microtitration with EDTA. A 100-/xL sample is treated with two drops of 2 M KOH, Cal-Red indicator is added, and the titration is performed with 0.00122 M EDTA, using a microburet. If 0.203 mL EDTA is required for titration, what is the level of calcium in the serum in mg/dL and in meq/L ... 

Antimony Trisulfide. Antimony(III) sulfide (antimony sesquisulftde) [1345-04-6] SbS, exists as a black crystalline soHd, stibnite [1317-86-8] and as an amorphous red to yeUow-orange powder. Stibnite melts at 550°C and has Ai i° 298 175 kJ/mol (—41.8 kcal/mol)) A°29g, 182 J/(182 mol-K) [43.5 cal/(43.5 mol-K)] for the amorphous soHd AH° 298 1 147 kJ/mol (—35.1 kcal/mol) (38). The crystal stmcture of stibnite contains two distiucdy different antimony sites and consists of two parallel Sb S chains that are linked together to form cmmpled sheets (two per unit cell). 

The abbreviations for the investigation methods are also taken from the nomenclature of Sillen and Martel 1 (76) aiex = anion exchange cal = calorimetry ciex = cation exchange dis = distribution between two phases est = estimate red = e.m.f. with redox electrode sp = spectrophotometry. Our selected data, rather limited in number, arise from the present status of the IAEA assessment of inorganic complexes of the actinides (12). 

The absorption spectra of the silicon(IV) naphthalocyanines follows the pattern already seen with the analogous zinc(II) (Section 9.22.12.1.4) and aluminum(III) (Section 9.22.13.2) derivatives 354 the red band is shifted about 100 nm further to the red, with intensification. Bis(trihex-ylsiloxy)silicon(IV) naphthalocyanine has Amax(PhH) = 776 nm (e = 650,000 M-1 cm-1) and <1>A 0.35 (oxygen-saturated benzene).389 The solution is fluorescent (main emission at 780 nm, Tf 2.85 ns) the triplet energy (ca. 22 k cal mol-1) is a little less than the energy of the first singlet state of dioxygen, and the process (Equation (9)) is reversible (cf. compounds (40) and (41), Section 9.22.10.2). 

Because of its indirect bandgap, bulk crystalline silicon shows only a very weak PL signal at 1100 nm, as shown for RT and 77 K in Fig. 7.9. Therefore optoelectronic applications of bulk silicon are so far limited to devices that convert light to electricity, such as solar cells or photodetectors. The observation of red PL from PS layers at room temperature in 1990 [Cal] initiated vigorous research in this field, because efficient EL, the conversion of electricity into light, seemed to be within reach. Soon it was found that in addition to the red band, luminescence in the IR as well as in the blue-green region can be observed from PS. 

Qf -93.5kcal/mol Heat Capacity 23.96 cal/deg/mol at 298°K sol in w, alkalies or aq KC1 si sol in glycerol or ethyleneglycol nearly insol in abs ale or abs acet. Potassium chlorate is si to moderately poisonous the principal toxic effects are the production of methemoglobin and the destruction of red blood corpuscles. The probable lethal dose is 50-500mg/kg or betw one teaspoonful and one ounce for a 150-lb man... 

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