The complete combustion of gaseous sucrose at a constant pressure absorbs 544 kj of heapt per mole of surcrose. write the balance thermochemical equation for the reaction

How many moles of carbon dioxide will form if 2.5 moles of c3h8 is burned

The excretory system,need answers for all: )

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.)