What will be the final temperature of a 22.0 g piece of iron (Cp = 25.09 J/K • mol), initially at 25°C, if it is supplied with 28.2 J from a stove?
q = mass x specific heat x (Tfinal-Tinitial).
Be careful with units. mass is in grams, specific heat is in J/mol. You need to change mass to mol Fe or Cp to J/g.