13.6
a) yes Pb is more reactive that Ag, Pb before Ag
b) no, Cu after H
c) yes, Cl2 is more active than I2
4) yes, Mg is more active
13.7 (as I think)
Al ³⁺ more active than Zn²⁺, Mn can react with Zn²⁺, but not with Al ³⁺ , because Mn after Al but before Zn
Concave is not a type of mechanical wave because it doesn’t need a medium for propagation.
BaSO4 is the correct formula for barium (ll) sulfate
Answer:
Oxygen, it's supposed to have six valenge electrons.
Explanation:
Count the dots on the oxygen atom, you'll see seven, but there's supposed to be six.
