When calcium carbonate reacts with hydrogen chloride, if the reaction occurs with 78.5% yield, what mass of carbon dioxide will be collected if 19.88g of caco3 is added to sufficient hydrogen chloride?

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

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.)

Nan element’s square on the periodic table, the number with the greatest numerical value represents the