After mixing for three hours, the product is extracted into dichloromethane and the solvent is removed to give 245 mg of an oil. Using the moles of our protected aldehyde calculated earlier (2.96) and the molecular weight of the product (102 g/mol) predict the theoretical 100% yield of the product in milligrams. Round to the tenths place.

the theoretical 100% yield of the product in milligrams is 302920 mg

Explanation:  

Given the data in the question;  

245 mg of an oil

Using the moles of our protected aldehyde calculated earlier (2.96)

the molecular weight of the product (102 g/mol) = 102000 mg/mol

so, the mass of aldehyde produced (100% yield) will be;

⇒ number of moles × molar mass

⇒ 2.96 mol × 102000 mg/mol

⇒ 302920 mol.mg / mol

⇒ 302920 mg

Therefore, the theoretical 100% yield of the product in milligrams is 302920 mg

water is used to store them because it would keep the radiation from getting out in the open and causing harm to the workers