1) How many molecules are found in each of the following? a) 1 lb of sucrose, C12H22O11 (table sugar)   b) 1.57 kg of N2O (anesthetic)

2) How many molecules are found in each of the following? a) 4x10^5 tons (t) of SO2 (produced by the 1980s eruption of Mount St Helens volcano)   b) 25.0 lb of SiO2 (major constituent of sand)

3) an elodea plant, commonly found in tropical fish aquaria, was found to produce 5.0 x10^22 molecules of oxygen per hour (h). What volume of oxygen (at STP) would be produced in an 8-h period?