Can someone help me to answer this correctly, please, and explain it. Please answer these 3 short questions, I don't have more money to buy more questions. These 3 questions are different.

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A 15.12 gram sample of iron is heated in the presence of excess sulfur. A metal sulfide is formed with a mass of 28.15 g. Determine the empirical formula of the metal sulfide. Enter the elements in the order Fe,S empirical formula = Use the References to access important values if needed for this question. A 22.60 gram sample of copper is heated in the presence of excess fluorine. A metal fluoride is formed with a mass of 29.35g. Determine the empirical formula of the metal fluoride. Enter the elements in the order Cu,F empirical formula = Use the References to access important values if needed for this question. A 18.42g sample of copper is heated in the presence of excess chlorine. A metal chloride is formed with a mass of 28.69 9. Determine the empirical formula of the metal chloride. Empirical formula