Final answer:
The boiling point of CoCl₂ is higher than 100.51°C because it produces three particles when dissolved in water. Therefore, the correct answer is option d) 220°C.
Step-by-step explanation:
The boiling point of a solution depends on the concentration of solute particles in the solution. In the case of CoCl₂, when the compound is dissolved in water, it dissociates into two ions, Co²⁺ and 2Cl⁻. This means that CoCl₂ will contribute three particles to the solution, raising its boiling point.
According to the information provided, the molal boiling point elevation constant for water is 0.51°C/m. Since CoCl₂ produces three particles, the boiling point elevation will be approximately three times larger than that of a 1.00 m NaCl solution, which is about 0.51°C. Therefore, the boiling point of CoCl₂ is expected to be higher than 100.51°C, the boiling point of a 1.00 m NaCl solution.
From the given options, the boiling point of CoCl₂ is closest to 220°C (option d).