C is wrong, the real answer is B: to add tartness, and the reason why is because citric acid comes from jam, jellies, and more! And that is why the answer B is the correct answer.
Hope this helped!
Nate
(P.S. if you buy jams and real the ingredients, it will say "citric acid." :))
Answer: Formula weight is the sum of weights of all the atoms in an empirical formula of a molecule. Molecular weight is the collection of weights of all the atoms in a molecular formula.
I would say it should be Einstein's famous equation of e=mc^2 which means energy =mass x the speed of light squared. With this equation Einstein showed that energy comes from a mass travelling at the speed of light squared which is a fundamental equation to explain physical phenomena.
