Question

Lead is found in Earth’s crust in several different lead ores. Suppose a certain rock is composed of 38.0% PbS (galena), 25.0% PbCO₃ (cerussite), and 17.4% PbSO₄ (anglesite). The remainder of the rock is composed of substances that don’t contain lead.

How much of this rock (in kg) must be processed to obtain 5.2 metric tons of lead? (A metric ton is 1000 kg.)  

Express your answer using two significant figures.

Answer 1