80.5%- The total mass of the compound is 18g (14.5 + 3.5) then divide the mass of magnesium by the total. easy way to remember is- (part/whole) x 100
You forgot one...and that happens to be the answer---> Accuracy
For soda their will be a chemical reaction the same as mentors and diet coke. In vinegar their will be no reaction...just smell funny for lemon juice their will be no reaction and the same with milk, it only reacts with coke because the chemicals inside of it also because it is fizzy and not still