What is the atomic number of zirconium? 39 40 41 42

Iwill give extra points to who gets this right

List four observations that indicate that a chemical reaction may be taking place

Click the button that shows the correct relationship of the electron affinities of the elements sodium and phosphorus. sodium’s electron affinity value is more negative than the electron affinity value of phosphorus. phosphorus’ electron affinity value is more negative than the electron affinity value of sodium. this information cannot be determined using the periodic table. answer is b on e2020.