A0.3 g piece of copper is heated and fashioned into a bracelet. the amount of energy transferred b copper is 66,300 j. if the specific heat of copper is 390 j/g "c, what is the change of the copper's temperature?

Let's assume that Copper has not changed its phase during this process.

we can use the heat equation,Q = mcΔT 
where Q is the amount of energy transferred (J), m is the mass of the substance (kg), c is the specific heat (J g⁻¹ °C⁻¹) and ΔT is the temperature difference (°C).

Q = 66300 Jm = 0.3 gc = 390 J g⁻¹ °C⁻¹ΔT = ?

By applying the formula,
66300 J = 0.3 g x 390 J g⁻¹ °C⁻¹ x ΔT
        ΔT = 566.67 °C

Hence, the temperature change of Copper during the heating process is 566.67 °C.