Which choice is an example of an endothermic process?
.conversion of steam to ice
.conversion of steam to water
.conversion of water to ice
.conversion of ice to steam

If you have 5.25 grams of methane (ch4), how many grams of co2 will you produce ?

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.)

Which statement best describes the function of enzymes?