Lead can be prepared from galena [lead(ii) sulfide] by first roasting the galena in oxygen gas to form lead(ii) oxide and sulfur dioxide. Heating the metal oxide with more galena forms the molten metal and more sulfur dioxide. Required:
a. Write a balanced equation for each step.
b. Write an overall balanced equation for the process.
c. How many metric tons of sulfur dioxide form for every metric ton of lead obtained?

Which statement is true according to the kinetic theory? a. molecules of different gases with the same mass and temperature always have the same average density. b. molecules of different gases with the same mass and temperature always have the same average volume. c. molecules of different gases with the same mass and temperature always have the same pressure. d. molecules of different gases with the same mass and temperature always have the same molecular mass. e. molecules of different gases with the same mass and temperature always have the same average kinetic energy.