Chem CE 95 MC no.29

Question

1. Citric acid is an electrolyte
2. When citric acid is dissolved in water, citric acid molecules become mobile.

When the second statement is not the explanation of the first statement?

Answer 1

The first statement is correct.
However, citric acid solution is a weak electrolyte. This is because citric acid is only partly (far below 100%) ionized in water to give hydrogen ions and anions.

The second statement is correct.
Since citric acid is only partly ionized in water. In citric acid solution, a small fraction of the citric acid molecules are ionized in water to give hydrogen ions, but most of the citric acid molecules still exist as molecules. Now, all of the hydrogen ions, anions and citric acid molecules are mobile in the solution.

The second statement is NOT the explanation of the first statement. Citric acid is an electrolyte because there are mobile ions (formed by ionization of citric acid) in the solution (but not because of the mobile molecules).

Answer 2

first statement is correct.
second statement is correct but is not a good explanation of first statement.




Citric acid is an electrolye because when citric acid is electrolysis, we can get to new substance at anode and catnode. ( we can get Hydrogen at catnode)