Consider the expected conductivities of CaCl2(aq) and Ca(OH)2(aq). Which of these can be expected to have the higher conductivity. Explain your reasoning.
CaCl2 should have a higher conductance than Ca(OH)2. Both have three ions when the same concn is measured but CaCl2 is much more soluble than Ca(OH)2.
To determine which compound, CaCl2(aq) or Ca(OH)2(aq), is expected to have the higher conductivity, we need to consider the dissociation of the compounds in water and their resulting ions.
CaCl2(aq) dissociates into Ca2+ ions and 2 Cl- ions:
CaCl2(aq) → Ca2+(aq) + 2 Cl-(aq)
Ca(OH)2(aq) dissociates into Ca2+ ions and 2 OH- ions:
Ca(OH)2(aq) → Ca2+(aq) + 2 OH-(aq)
The electrical conductivity of an aqueous solution depends on the concentration of ions in the solution. More ions lead to a higher conductivity because they can carry electrical charge.
In CaCl2(aq), the compound dissociates into three ions (one Ca2+ ion and two Cl- ions), while in Ca(OH)2(aq), it dissociates into three ions as well (one Ca2+ ion and two OH- ions).
Since both compounds produce the same number of ions when dissolved in water, they are expected to have similar conductivities.
In conclusion, CaCl2(aq) and Ca(OH)2(aq) are expected to have comparable conductivities since they dissociate into the same number of ions in water.
To determine which compound, CaCl2(aq) or Ca(OH)2(aq), is expected to have a higher conductivity, we need to consider the nature of the ions present in their respective solutions.
CaCl2 is an ionic compound composed of one calcium ion (Ca2+) and two chloride ions (Cl-) per formula unit. When dissolved in water (forming an aqueous solution), CaCl2 dissociates into its constituent ions: Ca2+ and 2Cl-. These ions are responsible for conducting electricity as they are charged particles that can freely move in the solution.
Ca(OH)2 is also an ionic compound, but it consists of one calcium ion (Ca2+) and two hydroxide ions (OH-) per formula unit. Similarly, when Ca(OH)2 is dissolved in water, it dissociates into its constituent ions: Ca2+ and 2OH-.
Now, to determine the conductivity, we need to consider the mobility of the ions in solution. The conductivity of an electrolyte solution depends on the concentration of ions and their mobility. Ions with higher mobility will conduct electricity more effectively.
In this case, we can determine the mobility of ions by considering their charge and size. Ca2+ is a small, highly charged ion, while Cl- is moderately sized with a single negative charge. On the other hand, OH- is large and has a single negative charge.
Due to its small size and higher charge, the Ca2+ ion tends to have higher mobility in solution compared to both the Cl- and OH- ions. This higher mobility allows Ca2+ ions to move more freely and conduct electricity more effectively.
Therefore, based on the ionic nature and mobility of the ions present, CaCl2(aq) is expected to have a higher conductivity compared to Ca(OH)2(aq).