Final answer:
To calculate x/2, where x represents the kilojoules absorbed when 7.45 g of metal chloride is dissolved in water, simply divide x by 2. Without the exact value of x, the specific calculation for x/2 cannot be performed.
Step-by-step explanation:
The question involves calculating the heat absorbed when a certain quantity of metal chloride is dissolved in water. If 7.45 g of metal chloride (in this case, calcium chloride), absorbs heat equivalent to x kilojoules, to calculate x/2 we simply divide the given amount of heat by 2. According to the information provided, the molar heat of solution (ΔHsoln) for calcium chloride is -82.8 kJ/mol. However, without knowing the molar mass of the metal chloride or the exact value of x, we cannot determine the specific quantity absorbed for 7.45 g of the metal chloride or perform the division of x/2. If the value of x were known, the calculation would involve basic arithmetic.