What mass of iodine would react with 48 grams of magnesium to make magnesium iodide?

Answer 1

Mg + I2 ==> MgI2
mols Mg = grams/molar mass
Using the coefficients in the balanced equation, convert mols Mg to mols I2. that's a 1:1 reaction.
Now convert mols Mg to grams. g = mols MgI2 x molar mass MgI2.

Answer 2

508 grams