Compute the number of electrons in a flake of pure gold valued at $0.15. Assume that the price of gold is $1762.0/troy oz. (1 troy oz = 31.1 g)
Sea-level atmospheric pressure is approximately 14.7 pounds per square inch. From this fact, we can deduce that a column of air one square inch in cross-section, measured from sea level to the top of the atmosphere, would weigh approximately 14.7 lb. Given that air has an average molar mass of 28.97 g, calculate the number of moles of air in the column.