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-1

The difficulty in answering 'classical' questions about the atom and its electrons (forces, speeds, whereabouts...) led to the development of quantum mechanics in the early 20th century. Nevertheless, for this particular issue we can push the classical understanding a bit further by considering electrons as tiny bar magnets resulting from spin. The unpaired ...


6

Theory guides and experiment decides (I. M. Kolthoff). Sometimes thermodynamics predicts a reaction but it does not occur very fast because its kinetics is slow. If you dissolve iron (III) chloride in pure denionized water, assuming it is from a fresh bottle, it will take hours to form a precipitate of iron hydroxides. Therefore, in order to perform this ...


-2

NaCl/ rocksalt lattice is a FCC structure The length of the cubic for FCC is taken as: a Volume of lattice is: a^3 Based on 1 atom +2 half atoms, the diagonal length is derived as Sqrt(2a^2 )= a sqrt 2 The diagonal length is made up of 2 atoms or total length is equals to 4r, where r is the radius of atom. Hence, r = (a sqrt 2) /4 OR a= 4r/ sqrt 2 APF of ...


4

Most of the $10$ compounds from your list simply do not exist. This is why they are not reported in your table. For example iron(III) iodide does not exist. When trying to produce it by mixing $\ce{Fe^{3+}}$ and $\ce{I-}$ ions, a redox chemical reaction occurs spontaneously according to : $$\ce{2 Fe^{3+} + 2 I^- -> 2 Fe^{2+} + I2}$$ For the other ...


5

In the case of magnesium chromate, good solubility in water has been known since 1931. From Hill et al. [1], citing [2]: The only figure on the solubility of the salt [as of 1940] appears to be that of Kohlraush[2], who reported that at 18°[C] 100 ml of saturated solution contained 60 g of magnesium chromate. Most of the other compounds listed, as ...


1

A picture is worth a thousand words. In the picture above, start with a mole of solid sodium and half a mole of Cl$_2$ gas, in the ground state. Then gasify the sodium with 107.3 kJ of heat, then ionize it with 496 kJ of energy, then dissociate Cl$_2$ to Cl radicals with 121.7 kJ, then allow the electron from the sodium to combine with the chlorine radical. ...


1

In aqueous solutions, $\ce{K3Fe(CN)6}$ and $\ce{Na2SO4}$ will completely dissociate: $$\ce{K3Fe(CN)6 (aq) -> 3 K+ (aq) + Fe(CN)6^3- (aq)} \tag1$$ $$\ce{Na2SO4 (aq) -> 2 Na+ (aq) + SO4^2- (aq)} \tag2$$ Thus, from the equation $(1)$, $c_\ce{K+} = 3c_\ce{Fe(CN)6^3-} = 3c_\ce{K3Fe(CN)6}$ and from the equation $(2)$, $c_\ce{Na+} = 2c_\ce{SO4^2-} = 2c_\ce{...


2

When ionic compounds dissolve in water, water molecules form a complex ion around the calcium cation. The presence of the hydroxide anion has a similar effect, though the polarities of the water ligands is reversed. Thus, dissolution of Ca(OH)2 in water is actually a chemical reaction. In some cases, complex ions may be more structured than the crystals of ...


-2

Entropy can be measured and aproached differently, (i) from an equation that relates entropy and Enthalpy to measure the heat of reaction, the remainder of the work done per degree of Temperature (°) is or if the change in enthalpy is measured then simply. In this case the Vector of entropy has a negative direction hence an endothermic process and the ...


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