13. A method for producing pure copper metal involves the reaction of copper(I) sulfide with oxygen gas to give copper metal and sulfur dioxide. Suppose the yield of this reaction is 87%. What mass of a copper ore consisting of 46% copper(I) sulfide must be mined in order to produce 1.0 x 103 kg (1.0 metric ton) of copper metal? A) 1.3 × 103 kg B) 1.4x 103 kg C) 1.5 x 103 kg D) 3.2 × 103 kg E) 8.0 × 103 kg Page 3