Which of the following is a weak electrolyte formula?

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Acetic acid is an example of a weak electrolyte even though it is highly soluble in water.

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A weak electrolyte is an electrolyte that does not completely dissociate in aqueous solution. The solution will contain both ions and molecules of the electrolyte. Weak electrolytes only partially ionize in water (usually 1% to 10%), while strong electrolytes completely ionize (100%). 

Weak Electrolyte Examples

HC2H3O2 (acetic acid), H2CO3 (carbonic acid), NH3 (ammonia), and H3PO4 (phosphoric acid) are all examples of weak electrolytes. Weak acids and weak bases are weak electrolytes. In contrast, strong acids, strong bases, and salts are strong electrolytes. Note a salt may have low solubility in water, yet still be a strong electrolyte because the amount that does dissolve completely ionizes in water.

Acetic Acid as a Weak Electrolyte

Whether or not a substance dissolves in water is not the determining factor in its strength as an electrolyte. In other words, dissociation and dissolution are not the same things.

For example, acetic acid (the acid found in vinegar) is extremely soluble in water. However, most of the acetic acid remains intact as its original molecule rather than its ionized form, ethanoate (CH3COO-). An equilibrium reaction plays a big role in this. Acetic acid dissolves in water an ionizes into ethanoate and the hydronium ion, but the equilibrium position is to the left (reactants are favored). In other words, when ethanoate and hydronium form, they readily return to acetic acid and water:

CH3COOH + H2O ⇆ CH3COO- + H3O+

The small amount of product (ethanoate) makes acetic acid a weak electrolyte rather than a strong electrolyte.

Which of the following is a weak electrolyte?A. \[N{a_2}C{O_3}\] B. \[KHC{O_3}\] C. \[{(C{H_3}COO)_2}Pb\] D.All of the above

Answer

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Hint: To solve this question, we must understand the meaning and characteristics of a weak electrolyte. Then we need to compare the properties of the compounds given to us to find the correct answer.

Complete Step-by-Step Answer:
Before we move forward with the solution of the given question, let us first understand some important basic concepts.
Weak electrolytes can be basically defined as those compounds which do not completely dissociate in aqueous solutions. To put this in simpler terms, we can say that weak electrolytes are those compounds which partly or very negligibly dissociate into their constituent ions, when they are mixed in aqueous solutions. These compounds only partially ionize in water.
Let us now discuss the options given to us:
A. \[N{a_2}C{O_3}\] : The molecular formula of \[N{a_2}C{O_3}\] or sodium carbonate is 106 g/mol. When measured at STP, only 34 g of sodium carbonate dissolves in water. This means that one mole of sodium carbonate cannot fully dissociate into one mole of water. Hence, it is a weak electrolyte.
B. \[KHC{O_3}\] : The molecular formula of \[KHC{O_3}\] or potassium bicarbonate is 100.115 g/mol. When measured at STP, only 22.4 g of potassium bicarbonate dissolves in water. This means that one mole of potassium bicarbonate cannot fully dissociate into one mole of water. Hence, it is a weak electrolyte.
C. \[{(C{H_3}COO)_2}Pb\] : The molecular formula of \[{(C{H_3}COO)_2}Pb\] or lead diacetate is 235.29 g/mol. When measured at STP, only 69.5 g of sodium carbonate dissolves in water. This means that one mole of lead diacetate cannot fully dissociate into one mole of water. Hence, it is a weak electrolyte.

Hence, Option D is the correct option

Note: On the other hand, a strong electrolyte is a solution/solute that completely, or almost completely, ionizes or dissociates in a solution. These ions are good conductors of electric current in the solution.

What is the formula of weak electrolyte?

HC2H3O2 (acetic acid), H2CO3 (carbonic acid), NH3 (ammonia), and H3PO4 (phosphoric acid) are all examples of weak electrolytes. Weak acids and weak bases are weak electrolytes.

Is ch3cooh weak electrolyte?

Answer and Explanation: Acetic acid is a weak acid as suggested by its low dissociation constant. This low dissociation constant of acetic acid makes its ionization in an aqueous solution very limited. With this, it can be considered that acetic acid is a weak electrolyte.

Is KCL a weak electrolyte?

Solution: Yes, potassium chloride is a strong electrolyte. As it dissociates completely into its ions on dilution.

Why is Na2CO3 a weak electrolyte?

Na2CO3 is a weak electrolyte as the solution is partially dissociated in the fused or aqueous solution state. PhNH+3Cl(aq.) Na2CO3(aq.)