Some Chemical Aspects of the Limnology of the Lakes in the Okoboji Region

The mineral content of several lakes, bogs, springs and ponds in the Lake Okoboji region show wide variation in quantity and ratio of dissolved salts. The dissolved Oxygen, alkalinity, conductance and pH of West Okoboji and East Okoboji have been measured at intervals during the summer months of 1937 and 1938. The thermocline develops slowly in West Okoboji, deep lake, and reaches full development late in July. This condition then remains for the remainder of the summer. Spirit Lake, East Okoboji, which are typical shallow lakes, develop thermoclines which are disturbed by strong winds. Occasionally hydrogen sulfide develops in the bays to such an extent that absorbed oxygen is completely removed from the water. The mineral content of the cold spring bog water, shows similarities in bogs widely separated. Some of these bogs contain sulfur bearing springs. The pH of a large number of pond waters was determined and compared with the algae growth present

Binary System with Acetamide: (1) Acetamide - Water (2) Acetamide - Naphthalene

The binary system acetamide and water, investigated by the solubility method, shows the formation of a hydrate of acetamide of composition (CH3CONH2)2H2O. The system is especially characterized by two solubility curves of acetamide in water, one lying ten to twelve degrees below the other. This is due to the two modifications of pure acetamide, with melting points at 80°C. and 69.4°C. In the more dilute solutions, supercooling can be carried to 80° below the crystalizing temperature in sealed tubes. The Binary System acetamide-naphthalene, investigated by the freezing point method shows two eutectics, one compound formation and a pair of immiscible liquids with a critical solution temperature

The Simultaneous Adsorption of Salt by Colloidal Aluminium Hydroxide

In a series of studies on the adsorption of electrolytes by colloidal suspensions of metallic hydroxides, Sen and his collaborators have measured the adsorption of a large number of electrolytes by various hydroxides. In determining the adsorption of acids by colloidal Ferric Hydroxide, he precipitated the colloid by means of KCl and NH4Cl inasmuch as the acids tended to stabilize the sol. The effect of the salts was considered to be negligible upon the adsorption of the acids

Binary Systems with Acetamide

The system acetamide - propionamide was investigated by the freezing point method. The solubility curve obtained showed a eutectic at approximately 0.5 mol. fraction. The experimentally determined solubility curve corresponds well with the ideal solubility calculated from the ideal equation

The Solubility of Copper Iodate in Aqueous Salt Solutions

The solubility of copper iodate in pure water and in solutions of potassium chloride, potassium sulphate, magnesium chloride and magnesium sulphate was measured

The System Potassium Chloride-Acetamide

The freezing point curve of acetamide solutions of potassium chloride is determined up to saturation at the freezing point

The Salt Effect of Certain Indicators in Slightly Buffered Solutions

The change in the colorimetric pH with changes in salt concentration is determined with reference to the quinhydrone electrode. The salts used caused a more alkaline reading with the quinhydrone electrode and a more acid reading with the colorimetric method. The effect is much more pronounced in the lower concentrations. The colorimetric pH does not change appreciably in concentrations from about 1 molar to saturation

The Effect of Impurities on the Physical Properties of Oxychloride Cements

The rapidly increasing use of Stucco, a cement made by mixing magnesite with a solution of magnesium chloride, as an exterior for dwelling houses has given rise to an interesting study of its chemical and physical properties. As usually applied, the stucco is made according to the specifications of the Committee on Specifications for Plastic Magnesite, which recommended the following mixture to be standard: One part by weight of plastic calcined Magnesite; Two parts by weight of Standard Ground Silica; Five parts by weight of Standard Ottawa Sand. This is then mixed with a 22 degree Baume solution of magnesium chloride to the proper consistency. Various colored oxides may be added to color the cement as desired. The cementing properties of such mixture are due to the formation of an oxychloride compound of magnesium by the interaction between magnesite and the magnesium chloride solution, the sand acting only as a filler or as an attachment for the cement crystals