In order for a chemical reaction to take place, a certain amount of must be present. a. heat b. friction c. chemicals d. energy

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05.06 percent yield lab report answers

What is the composition, in atom percent, of an alloy that consists of 4.5 wt% pb and 95.5 wt% sn? the atomic weights for pb and sn are 207.19 g/mol and 118.71 g/mol, respectively.(a) 2.6 at% pb and 97.4 at% sn(b) 7.6 at% pb and 92.4 at% sn(c)97.4 at% pb and 2.6 at% sn(d) 92.4 at% pb and 7.6 at% sn

Which of the following compounds does not contain molecules? question 2 options: co2 h2 nacl h2o