A solution is made using 80.1 g of toluene (MM=92.13 g/mol) and 80.0 g of benzene (MM=78.11 g/mol). What is the mole fraction of the toluene in the solution?

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.)

List the path of the respiratory system

Calculate the concentration of all species in a 0.165 m solution of h2co3.