Curious Carl and his lab partner added small pieces of various metals to HCl. Magnesium (Mg) and zinc (Zn) reacted vigorously with HCl, releasing hydrogen gas. This equation represents the reaction of zinc in hydrochloric acid.

Zn + 2HCl → ZnCl2 + H2
What is the half reaction for the reduction of hydrogen in the reaction?

A) 2HCl → + 2e- + H2(g)
B) H + Cl → + 2e- + H2(g)
C) 2H+ + 2e- → H2(g)
D) 2H+ - 2e- → H2(g)

Aaspirin has a density of 1.40 g/cm^3 what is the volume in cubic centimeters of a tablet weighing 320 mg?

Problem page combustion of hydrocarbons such as pentane ( c5 h12 ) produces carbon dioxide, a "greenhouse gas." greenhouse gases in the earth's atmosphere can trap the sun's heat, raising the average temperature of the earth. for this reason there has been a great deal of international discussion about whether to regulate the production of carbon dioxide.(a) write a balanced chemical equation, including physical state symbols, for the combustion of liquid pentane into gaseous carbon dioxide and gaseous water. (b) suppose 0.350 kg of pentane are burned in air at a pressure of exactly 1 atm and a temperature of 20.0 degree c. calculate the volume of carbon dioxide gas that is produced. be sure your answer has the correct number of significant digits.

Word equation for k(s)+h2o(l) yield koh(aq) + h2(g)