Acid‒base reaction
... does not restrict acidity to hydrogen-containing compounds, but his approach, published in 1938, was even more general than Lewis theory.[2] Usanovich's theory can be summarized as defining an acid as anything that accepts negative species or donates positive ones, and a base as the reverse. This pu ...
... does not restrict acidity to hydrogen-containing compounds, but his approach, published in 1938, was even more general than Lewis theory.[2] Usanovich's theory can be summarized as defining an acid as anything that accepts negative species or donates positive ones, and a base as the reverse. This pu ...
Stoichiometry Notes
... At STP/NTP one mole of any gas contains 22.4 L i.e. at 273 K and 1 atm pressure. Mole concept is based on balanced chemical reaction. If amounts of both reactants are given then find the limiting reagent. It is that reagent which is consumed completely in a irreversible chemical reaction. Class Disc ...
... At STP/NTP one mole of any gas contains 22.4 L i.e. at 273 K and 1 atm pressure. Mole concept is based on balanced chemical reaction. If amounts of both reactants are given then find the limiting reagent. It is that reagent which is consumed completely in a irreversible chemical reaction. Class Disc ...
Solution - HCC Learning Web
... of the substance is CaCl2(aq). Sodium carbonate is composed of Na+ ions and CO32– ions; hence, an aqueous solution of the compound is Na2CO3(aq). In the molecular equations for precipitation reactions, the anions and cations appear to exchange partners. Thus, we put Ca2+ and CO32– together to give C ...
... of the substance is CaCl2(aq). Sodium carbonate is composed of Na+ ions and CO32– ions; hence, an aqueous solution of the compound is Na2CO3(aq). In the molecular equations for precipitation reactions, the anions and cations appear to exchange partners. Thus, we put Ca2+ and CO32– together to give C ...
NATIONAL HIGH SCHOOL CHEMISTRY EXAMINATION (1995
... 19. Pure solid ammonium carbamate (NH4 CO2 NH 2 ) is put into a vessel which already contained ammonia at a partial pressure of 10.1 kPa. The solid ammonium carbamate is allowed to dissociate according to the equation: NH 4 CO2 NH 2 (s) → 2 NH 3 (g) + CO2 (g) ...
... 19. Pure solid ammonium carbamate (NH4 CO2 NH 2 ) is put into a vessel which already contained ammonia at a partial pressure of 10.1 kPa. The solid ammonium carbamate is allowed to dissociate according to the equation: NH 4 CO2 NH 2 (s) → 2 NH 3 (g) + CO2 (g) ...
IChO 2012
... Pyrolysis of this compound leads to the generation of H2 gas and polyborazylene. H3N–BH3(s) 2.5 H2(g) + (polyborazylene, BNH) (If an efficient and low-cost method can be found to regenerate H 3N–BH3 from BNH, the substance could be used to generate hydrogen in fuel-cell powered applications.) Furt ...
... Pyrolysis of this compound leads to the generation of H2 gas and polyborazylene. H3N–BH3(s) 2.5 H2(g) + (polyborazylene, BNH) (If an efficient and low-cost method can be found to regenerate H 3N–BH3 from BNH, the substance could be used to generate hydrogen in fuel-cell powered applications.) Furt ...
Liquid–liquid extraction
Liquid–liquid extraction (LLE) consists in transferring one (or more) solute(s) contained in a feed solution to another immiscible liquid (solvent). The solvent that is enriched in solute(s) is called extract. The feed solution that is depleted in solute(s) is called raffinate.Liquid–liquid extraction also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid into another liquid phase. Liquid–liquid extraction is a basic technique in chemical laboratories, where it is performed using a variety of apparatus, from separatory funnels to countercurrent distribution equipment. This type of process is commonly performed after a chemical reaction as part of the work-up.The term partitioning is commonly used to refer to the underlying chemical and physical processes involved in liquid–liquid extraction, but on another reading may be fully synonymous with it. The term solvent extraction can also refer to the separation of a substance from a mixture by preferentially dissolving that substance in a suitable solvent. In that case, a soluble compound is separated from an insoluble compound or a complex matrix.Solvent extraction is used in nuclear reprocessing, ore processing, the production of fine organic compounds, the processing of perfumes, the production of vegetable oils and biodiesel, and other industries.Liquid–liquid extraction is possible in non-aqueous systems: In a system consisting of a molten metal in contact with molten salts, metals can be extracted from one phase to the other. This is related to a mercury electrode where a metal can be reduced, the metal will often then dissolve in the mercury to form an amalgam that modifies its electrochemistry greatly. For example, it is possible for sodium cations to be reduced at a mercury cathode to form sodium amalgam, while at an inert electrode (such as platinum) the sodium cations are not reduced. Instead, water is reduced to hydrogen. A detergent or fine solid can be used to stabilize an emulsion, or third phase.