Many compounds are only partially dissociated into ions in aqueou...

Question

Many compounds are only partially dissociated into ions in aqueous solution. Trichloroacetic acid (CCl₃CO₂H), for instance, is partially dissociated in water according to the equation

CCl₃CO₂H (aq) → H⁺ (aq) + CCl₃CO₂⁻ (aq)

For a solution prepared by dissolving 1.00 mol of trichloroacetic acid in 1.00 kg of water, 36.0% of the trichloroacetic acid dissociates to form H⁺ and CCl₃CO₂⁻ ions.

What is the total concentration of dissolved ions and molecules in 1 kg of water?

Accepted Answer

Hello. In this problem, we are told the dichloroacetic acid partially dissociates into irons and water. A solution of dichloroacetic acid was prepared from 1.50 molds of dichroic acid and 1.50 kg of water. We're asked to calculate the total concentration of molecules and dissolved ions in 1.50 kg of water. If 90% of the dichloroacetic acid dissociates into ions, we are provided with the equation that describes the dissociation of dichloroacetic acid. It tells us that for every one mole of dichloroacetic acid that dissociates, we get one mole of hydron nines and one mole of dichloroacetate anions. We are provided with four possible answers. All four answers give us the quantity of water as 1.50 kg. What differs is the moles of ions and molecules answer A states, we have 1.50 moles of vines and molecules answer B states 1.79 moles of vines and molecules answer C states, three moles of vines and molecules and answer D states 4.50 moles of vines and molecules to determine the molecules. We need to know the quantity of dichloroacetic acid that is unassociated. To determine the quantity of ions, we need to know the amount of dichloroacetic acid that does dissociate. So we will begin by finding the moles dichloroacetic acid that dissociates from there. We can make use of the dissociation equation to determine the mold of. And once we know how much of the dichloroacetic acid associates, we can determine the moles of dichloroacetic acid. The remains unassociated. Starting with our quantity of dichloroacetic acid, we have 1.50 moles of dichloroacetic acid that was put into the water. The 19% of the dichroic acid associates can be rewritten as 19.0 moles of diplo acetic acid associates for every one mole of di acetic acid are mold of diplo acetic acid cancels and this is equal to 0. moles of dichloroacetic acid that dissociates. And when the molds of dichloroacetic acid that dissociates, we can determine quantity of ions based on the dissociation equation. For every one mole of dichloroacetic acid that associates. We get two moles of irons, we get one mole of hydron ions and we get one mole of dichloroacetate anions are moles of chloral acetic acid that dissociates cancels and this is equal to zero point 570 moles of irons. We began with 1.50 moles of dichloroacetic acid. We found that 0.285 moles of dichloroacetic acid will dissociate. So that then means that the remaining amount of 1. molds of like Chlo acetic acid remains unassociated and therefore exists as molecules. You can then find our total moles of molecules and ions. We have 0.570 moles of irons and 1.215 mold of dichloroacetic acid that is unassociated. It exists as molecules. Our total number of moles of ions and molecules equal to 1.79 moles of molecules and ions referring back to our possible answers. We see that this corresponds with answer B thanks for watching. Hope this helped.

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