1.) why were coins originally made from precious metals such as gold or silver rather than cheaper metals such as copper? 2.) what is the major difference in metal composition of canadian coins compared with american ones?

What is an example of a physical property?

At 450 mm hg a gas has a volume of 760 l, what is its volume at standard pressure

16. why must the number of electrons lost equal the number of electrons gained in every redox reaction? use 3 – 4 sentences in your own words to address this question. 18. what type of radiation is emitted when chromium-51 decays into manganese-51? show the nuclear equation that leads you to this answer. 19. a radioactive nucleus alpha decays to yield a sodium-24 nucleus in 14.8 hours. what was the identity of the original nucleus? show the nuclear equation that leads you to this answer.