Moles of Cu in 7.8 * 10^21 atoms of Cu

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.