a pure compound because an element is untouched and is just itself
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
How many protons are in an isotope of sodium with a mass number of 25? 11
Because the moon orbits the earth and when the moon gets in front of the sun it blocks the sunlight and then it becomes night
