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The Schulze–Hardy rule states that the de stabilising power of an electrolyte is primarily due to the valence of its counter ion (ion that has opposite charge to the colloidal surface) [20], [24].
What do you mean by Hardy Schulze rule?
> Hardy Schulze rule states that the amount of electrolyte required for the coagulation of a definite amount of a colloidal solution is dependent on the valency of the coagulating ion. Coagulation is generally brought about by the addition of electrolytes.
What is hardy Schulze rule Explain with examples?
The coagulating or flocculate capacity of an electrolyte increases with increase in charge is known as Hardy – Schulze law. Example 1: To coagulate a negative sol, the coagulating capacity of positive ion is Al+3 > Mg+2 > Na+ Example 2: To coagulate a positive sol the coagulating capacitor of negative ion.
What is flocculating ion?
Coagulation or precipitation:-it is a process of aggregating together the colloidal particle so as to change them into large sized particles which ultimately settles as a precipitate. The ion which is responsible for neutralization of charge on the colloidal particles is called the coagulating ion or Flocculating ion.
What modifications do you suggest in Hardy Schulze rule?
Thus, Hardy-Schulze law can be modified in terms of the polarising power of the flocculating ion. Thus, the modified Hardy-Schulze law can be stated as ‘the greater the polarising power of the flocculating ion added, the greater is its power to cause precipitation. ‘.
What is flocculation value?
Flocculation value is defined as the minimum concentration required of an electrolyte to cause the coagulation or flocculation of a solution. Flocculation value is inversely proportional to the coagulating power of the ion.
What happens when dialysis is prolonged?
Due to this removal of electrolytes, the colloidal particles become unstable and will lead to the process of coagulation. Note:Coagulation is a process in which the molecules of the colloidal solution combine to form molecules having a larger size.
What do you mean by Peptization?
Peptization or deflocculation is the process of converting precipitate into colloid by shaking it with a suitable electrolyte called peptizing agent. When colloidal particles bear a same sign electric charge, they mutually repel each other and cannot aggregate together.
What do you understand by gold number?
The Gold Number is the minimum weight (in milligrams) of a protective colloid required to prevent the coagulation of 10 ml of a standard hydro gold sol when 1 ml of a 10% sodium chloride solution is added to it. It was first used by Richard Adolf Zsigmondy.
What is zeta potential class 12th Chemistry?
Hint: Zeta potential is also known as Electrokinetic. It is used to define or explain the process of preferential adsorption of ions from solution in the electrical charge on colloidal particles. There are two layers: the fixed layer and the diffused layer.
What is the difference between flocculant and coagulant?
Flocculants differ from coagulants in that they are often polymers, whereas coagulants are typically salts. Generally speaking, anionic flocculants are used to catch mineral particles while cationic flocculants can capture organic particles.
How do flocculating agents work?
Flocculating agents are either inorganic salts or water-soluble organic polymers. They act by shrinking the ionic double layer, or neutralizing the surface charge of suspended particles, or bridging between particles. The type of flocculant used depends on the type of solid–liquid separation being performed.
Why is flocculation important?
Applying flocculation ensures a high flux over filtration units as well as efficient and cost effective separation of cell material from supernatant. Used water can contain significant amounts of suspended particulate matter, which often takes long to sediment.
Which has maximum flocculation value?
Lower the coagulation value, more efficient is the electrolyte in causing coagulation of sol. We can say coagulation value is inversely proportional flocculation value. having lowest charge will have minimum power and hence have maximum flocculation value. Thus, the correct option is C.
How do you calculate flocculating value?
Complete step by step solution: “The minimum concentration of an electrolyte that is required to cause the coagulation or flocculation of a sol is known as flocculation value.” It is expressed in terms of millimoles per litre. 2 mL of 1 M NaCl contains 2 / 1000 mol = 2 millimole.
Which has minimum flocculation value?
The minimum concentration of an electrolyte required to cause coagulation of a sol is called its flocculation value. It is expressed in millimoles per litre. If the flocculation value of MgSO4 for standard As2S3 sol is 3.33.
What happens when dialysis is stopped?
Without dialysis, toxins build up in the blood, causing a condition called uremia. The patient will receive whatever medicines are necessary to manage symptoms of uremia and other medical conditions. Depending on how quickly the toxins build up, death usually follows anywhere from a few days to several weeks.
What happens when electric field is applied to colloidal solution?
What happens when electric field is applied to colloidal solution? Answer: When electric potential is applied to colloidal solution, the colloidal particles move towards one or other electrode. The movement of colloidal particles under an applied electric potential is called electrophoresis.
What are associated colloids given an example?
Soap + Water: The colloidal solution of soap and water is an example of associated colloid. Rubber + benzene: It is an example of macromolecular colloids.
What is Peptization give an example?
Peptization is the method of producing stable colloids using an electrolyte to split up and distribute a precipitate into the colloids. Example: When the ferric chloride is added to the precipitate of ferric hydroxide, the hydroxide precipitate transfer to the sol by absorbing ferric ions.
How Peptization can be avoided?
Peptization should be avoided. (Peptization is the process by which a coagulated precipitate is returned to its colloidal state.) Peptization can be minimized by washing a precipitate with a solution of an electrolyte that is volatilized during an ensuing drying step.
What is Peptization and its causes?
Cause of peptization: As the electrolyte is added to a freshly precipitated substance, the particles of the precipitate preferentially adsorb one particular type of ions of the electrolyte and get dispersed due to electrostatic repulsion.
