¿Cortar árboles de un bosque asegurando luego volver a sembrar es una actividad sostenible? es un examen plz

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.)

Calculate the ph of a .10m nh4cl solution. the kb value for nh3 is 1.8×10^-5

What volume of 0.500 mol/l hydrochloric acid, hci (aq) is required to react completely with 1.00 g of aluminum hydroxide, ai(oh)3 (s)?