Cations sodium

Transfer of an electron from a sodium atom to a chlorine atom yields a sodium cation and a chloride anion both of which have a noble gas electron configuration... 

Fig. 3. Model of the crystal structure of the mineral mordenite showing the main channel formed by 12-membered ring and small channels which contain some of the sodium cations. Synthetic types of mordenite exhibit the adsorption behavior of a 12-membered ring, whereas the mineral does not, probably...

Selective absorption of durene from heavy gasoline (bp 150—225°C) is possible using a version of UOP s Sorbex technology where the X zeoHte is made selective for durene by replacing the exchangeable sodium cations with lithium ions (16). 

Fig. 12. Salt retention by coUoidal particles. The curved dashed and soHd lines represent the surface of a negatively charged siUca particle. Around this there is a layer of counter sodium cations outside there is a layer in which sulfate anions (Q) are more concentrated than in the bulk solution.

Calcium and/or Magnesium with Cation Exchanger (Insoluble) + Sodium Chloride (Soluble) = Sodium Cation Exchanger (Insoluble) + Calcium and/or Magnesium Chlorides (Soluble). 

Calcium, Magnesium andlor Sodium Bicarbonates (Soluble) + Hydrogen Cation Exchanger (Insoluble) = Calcium, Magnesium and/or Sodium Cation Exchanger (Insoluble) + Water + Carbon Dioxide (Soluble Gas). 

It is interesting to note that although the first examples of template effects were observed in nitrogen macrocycles (see chapter 2) no template effect appears to operate in the synthesis of 72. Richman and Atkins note this in their original report . The authors replaced the sodium cation with tetramethylammonium cations and still obtained greater than 50% yield of tetra-N-tosyl-72. Shaw considered this problem and suggested that because of the bulky N-tosyl groups, .. . the loss of internal entropy on cyclization is small He offered this as an explanation for the apparent lack of a template effect in the cyclization. 

Cholanic acid also possesses the ability of transporting cations across a lipophilic membrane but the selectivity is not observed because it contains no recognition sites for specific cations. In the basic region, monensin forms a lipophilic complex with Na+, which is the counter ion of the carboxylate, by taking a pseudo-cyclic structure based on the effective coordination of the polyether moiety. The lipophilic complex taken up in the liquid membrane is transferred to the active region by diffusion. In the acidic region, the sodium cation is released by the neutralization reaction. The cycle is completed by the reverse transport of the free carboxylic ionophore. 

Table 8. Stability constants and competitive transport ability of ionophores (50-57) for potassium and sodium cations...

Structural characteristics of compounds with X Me = 8 are collected in Table 17. Na3NbF8 and Na3TaF8 compounds that form similar crystal structure [77], The structure of Na3TaF8 was determined by Hoard et al. [136], by means of X-ray diffraction of a single crystal. Na3TaF8 is composed of sodium cations and isolated complex ions TaF83, in an Archimedean antiprism configuration, as shown in Fig. 23. 

FIGURE C.3 An ionic solid consists of an array of cations and anions stacked together. This illustration shows the arrangement of sodium cations (Na+) and chlorine anions (chloride ions, Cl-) in a crystal of sodium chloride (common table salt). The faces of the crystal are where the stacks of ions come to an end. 

J.I3 Na As04 is a salt of a weak base that can accept more than one proton, (a) Write the chemical equations for the sequential proton transfer reactions of the anion with water. Identify the acid and the base in each reaction, (b) If 35.0 g of Na3As04 is dissolved in water to make 250.0 ml. of solution, how many moles of sodium cations are in the solution ... 

In dioxane NafMeBCjHs] reacts with (COIjCKNHjIj to give NaKMeBCsH )-Cr(CO)3] 2 dioxane. The sodium cation can be substitutedby [Ph4P] or Hg. ... 

The presence of ions in solution is what gives a sodium chloride solution the ability to conduct electricity. If positively and negatively charged wires are dipped into the solution, the ions in the solution respond to the charges on the wires. Chloride anions move toward the positive wire, and sodium cations move toward the negative wire. This directed movement of ions in solution is a flow of electrical current. Pure water, which has virtually no dissolved ions, does not conduct electricity. Any solution formed by dissolving an ionic solid in water conducts electricity. Ordinary tap water, for example, contains Ionic Impurities that make It an electrical conductor. 

For sodium cations and chloride anions, q = + and q2 — - 1. To complete the calculation, we need to know how closely the ions approach each other before their mutual attraction is balanced by electron cloud repulsion. In the sodium chloride crystal this distance is 313 pm. Using this value for r, we can calculate the energy released in... 

Table 8 5 shows that each of the four common s-block ions is abundant not only in seawater but also in body fluids, where these ions play essential biochemical roles. Sodium is the most abundant cation in fluids that are outside of cells, and proper functioning of body cells requires that sodium concentrations be maintained within a narrow range. One of the main functions of the kidneys is to control the excretion of sodium. Whereas sodium cations are abundant in the fluids outside of cells, potassium cations are the most abundant ions in the fluids inside cells. The difference in ion concentration across cell walls is responsible for the generation of nerve impulses that drive muscle contraction. If the difference in potassium ion concentration across cell walls deteriorates, muscular activity, including the regular muscle contractions of the heart, can be seriously disrupted. 

Sodium cations 12 edges cation/edge) + 1 in center = 4 Na" cations ionic soiids have the same unit ceii structure as the sodium chioride iattice. Exampies are aii the haiides of Li, Na, K" ", and Rb, as weii as the oxides of Mg , Ca, Sr, and Ba. ... 

All sodium salts are soluble, and so are all nitrate salts, so It makes sense that neither of these ions participates in a solubility equilibrium. Furthermore, nitrate and sodium cations are neither acidic nor basic, so it makes sense that neither participates in an acid-base equilibrium. 

The original solution contains water and acetic acid molecules. Adding sodium acetate introduces two new major species, acetate anions and sodium cations. Thus, the resulting buffer solution has four major species H2 O, Na , CH3 CO2, and CH3 CO2 H. 

NaOCl Sodium hypochlorite is ionic, containing Na cations and OCl anions. The sodium cation has oxidation number equal to its charge, +1. In the anion, oxygen is -2 (Guideline 4), so chlorine must be +1 for the sum of the oxidation numbers to match the -1 charge of the hypochlorite anion (Guideline 2). 

Because carotenes lack heteroatoms such as oxygen to which protons or sodium cations might attach, no ions are usually detected for these hydrocarbon compounds during ESI in positive mode, although protonated molecules and sodium adducts were observed for xanthophyUs under normal conditions with MeOH, MTBE, and H2O as a mobile phase from HPLC. Addition of a heptafluorobutanol oxidant at 0.1 or 0.5% produced abundant molecular ions of p-carotene with high reproducibility. Substitution of MeOH for acetonitrile produced similar limits of detection. ... 

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