Final answer:
To calculate the mass of Li2SO4 needed to make 750 cm³ of a Li+ ion solution, we need to determine the number of moles of Li+ ions in the solution. From the given information, the concentration of Li+ ions is 30 mg/cm³. Using dimensional analysis, we can calculate the number of moles of Li+ ions in the solution.
Step-by-step explanation:
To calculate the mass of Li2SO4 needed to make 750 cm³ of a Li+ ion solution, we need to determine the number of moles of Li+ ions in the solution. From the given information, the concentration of Li+ ions is 30 mg/cm³. To convert this to moles, we need to know the molar mass of Li+.
Since Li+ is formed from Li, the molar mass of Li is 6.94 g/mol. Therefore, the molar mass of Li+ is also 6.94 g/mol. Using dimensional analysis, we can calculate the number of moles of Li+ ions in the solution as follows: Moles of Li+ = (Concentration of Li+ ions * Volume of solution) / Molar mass of Li+