What is the relationship between elemental analysis and empirical formula?

If the mass of the products measured 120g what would the mass of the reactants a. 30g b. 60g c. 120g d. 240g

This question is about electrolysis. metal spoons can be coated with silver. this is called electroplating. suggest one reason why spoons are electroplated?

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?