In cement manufacturing industry the material calcium carbonate is decomposed to calcium oxide and carbon dioxide using high temperature however due to temperature distribution difference the raw material is not decomposed with one pass operationin the reactor. the recycle of unconverted raw material is needed and a portion of reactor out put is recycled. carbon dioxide is only removed from the reactor in one stream and the overall product is collected in the product stream. the feed flow rate is 1kg/h and the overall conversion is in product stream assume that the mass flow rate ratio of the recycle stream to product stream is 0.1
the reaction is caco3 → cao + co2
a. determine the mass flow rates of gas stream and product stream
b. the mass fractions of the product stream
c. the mass flow rates of the product stream.

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

Which metal exist in liquid state and can be cut with knife ?

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)