Summary of Lesson on Complex Salts

 In the past two days, we have been looking at the concept of complex salts and I want us to tie it up today so that we can look at other topics also. I will recap the highlights of our discussion to make it easier for you to remember the key points that we have mentioned in the last two days.


I told you that a complex salt contains a complex cation or complex anion or both. The complex cation or anion does have a coordination sphere in which ligands which may be anionic or neutral are bonded to a central metal atom/ion covalently. This is called the coordination sphere of the complex ion. 


The number of ligands found in the coordination sphere is the coordination number of the central atom/ion. The complex ion often have ions that balance the charges and these are called counter ions and are located outside the coordination sphere of the complex ion. The bonding between the complex ion and the counter ions is entirely ionic in nature.


The geometry of the complex ions depend on the number of ligands that are attached to the central metal atom/ion, electronic effects (such as the well known Jahn – Taller effect), steric effects(when bulky ligands are involved) and symmetry of the complex (the point group to which the complex belongs). 


Complex salts often have color for a number of reasons. These reasons would be fully covered when we are discussing coordination chemistry in detail. However, some of these reasons may include;

1) Charge transfer

2) Weak d - d electronic transition

3) A ligand that contains a chromophore. 


Other examples of complex salts include those listed in the image attached to this post. Complex salts are used in dyeing of fabrics, in food preservation, in catalysis and as drugs. 


Tomorrow we shall go further in our discussion about salts by looking generally at the uses of salts. See you then!


Hope you enjoyed our lesson today?

Follow  our page  and share!

Do you have assignments, term papers, projects and difficult homework questions? Contact us for help now! We also offer home and remote tutoring services to students at all levels in science subjects.




Comments

Post a Comment

Popular posts from this blog

Definition of acids 2 - Introduction to Lewis Acids

Image
 Hello fam! Welcome to today’s lesson. We started to look at the concept of acid definition in yesterday’s lesson. We saw yesterday that acids have been defined by Arrhenius and BrØnsted – Lowry. The Arrhenius definition is limited in the sense that it does not account for behavior of acids in nonaqueous media. Did you try the assignment yesterday? The answers are attached to this post. I believe that the concept of proton donation is now clear to you after looking at the images attached. Reach out to me if you have any challenge. Now let us talk about the Lewis definition of acids. This definition of acids was put out by G. N Lewis in 1923. There is a foundation that we need in order to have an understanding of the idea that was put forward by Lewis.  There is something called an orbital in an atom. It is a region in space where there is a high probability of finding the electron. Now let us assume that your office is at No.38 Bronx street. I may not find you everywhere in the compoun
Read more

Calculations on pKa and pH

Image
 Hello! I heartily welcome you all to today’s lesson. We are going to look at the last two calculations that pertain to pH, acids and bases today and tomorrow we would commence our discussion on salts to pave way for a discussion on buffers. I hope all the topics so far are making sense? Your feedback would be highly appreciated. Example 8; What is the pH of 0.2 M solution of sodium acetate. The pKa of acetic acid is 1.8 * 10^-5. Solution; We have that the hydrolysis of sodium acetate occurs as follows; CH3CH2COONa(aq) <-> CH3CH2COO^-(aq) + Na^+(aq)    CH3CH2COO^-(aq) + H2O(l) <-> CH3CH2COOH + OH^-(aq) We can see that that the acetate ion acted as a base hence it accepted a proton. We would have to obtain the Kb Kb = 1 * 10^-14/Ka Kb = 1 * 10^-14/1.8 * 10^-5 Kb = 5.6 * 10^-10 Setting up the ICE TABLE, we have that;          CH3CH2COO^-(aq) + H2O(l) <-> CH3CH2COOH + OH^-(aq) I            0.2                                                      0                       
Read more

Bonding in Complex Salts

Image
 Hello! yesterday, we started looking at the complex salt which we called tetramine copper II chloride with the formula; [Cu(NH3)4]Cl2. We did say that this is a complex salt because of the presence to the complex cation [Cu(NH3)4]^2+. I want to state that if we had a complex anion, the salt would also be a complex salt. A typical example of this is; K4 [Fe(CN)6]. The complex ion is  [Fe(CN)6]4- which is anionic and the counter ions in this case are potassium cations. I told you that we will look at the bonding in the complex salt [Cu(NH3)4]Cl2 and why it does not produce simple ions in water. I will try to explain the basics of the concept today as we would still look at coordination chemistry in more detail sometime later.  Now, the complex salt [Cu(NH3)4]Cl2 has both ionic and covalent bonds. The four ammonia molecules are attached to the central copper II ion by a coordinate covalent bond(see the page timeline for an explanation of what a coordinate covalent bond is). We showed the
Read more