a compound of carbon, hydrogen, and nitrogen with a mass of 28.72 g was found to contain 7.924 g of carbon, 0.3304 g of hydrogen, and the rest is nitrogen. determine the empirical formula

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)