How can you tell one element from another?

Which formula can be used to calculate the molar mass of hydrogen peroxide

Which fact represents evidence for the big bang theory?

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.