In a hydrate of CoCl2, experimental analysis determined that there are 6 moles of water per formula unit. What is the correct formula for this hydrate?

• A. CoCl2 · 2H2O
• B. CoCl2 · 6H2O
• C. CoCl2 · 4H2O
• D. CoCl2 · H2O

Answer: (B)

Verified step by step guidance

1. Understand that a hydrate is a compound that includes water molecules integrated into its crystal structure, typically written as CoCl2 · xH2O, where x is the number of water molecules per formula unit.
2. Identify from the problem that the experimental analysis shows there are 6 moles of water per formula unit of CoCl2, meaning x = 6 in the hydrate formula.
3. Write the general formula for the hydrate using the given information: CoCl2 · 6H2O.
4. Compare this formula to the options provided to confirm which matches the number of water molecules determined experimentally.
5. Conclude that the correct formula for the hydrate, based on the experimental data, is CoCl2 · 6H2O.