june 2001 q14 - C. the gas released is obviously hydrogen because the metal will displace hydrogen from steam. steam is reduced because the H has gained an electron.
nov 2001 - 21 - A. Calcium oxide + HCl --> Calcium chloride + water. litmus red (acid) to blue (excess CaO)
nov 2003 - 16) B, lead oxide is reduced, lead remains, H20 (steam) dries up and adds to the drying agent.
19) C, neutralization because of acid + base. filtration at last.
26) B, hydrogen will displace copper.
june 04 - 9 - A, perfectly balanced
14) D - combustion
26) A. electrolyzing is used for very reactive metals. unreactive metals occur naturally