Why might someone write their postcode on a tv or computer using a pen with fluorescent ink that is not visible in normal light?

Which element in the third period would you expect to have the larger atomic radius, sodium (na) or sulfur (s)? a. sodium, because it has a higher effective nuclear charge attracting electrons in fewer energy levels. b. sodium, because it has fewer protons attracting electrons in the same energy levels. c. sulfur, because it has more protons attracting electrons in more energy levels. d. sulfur, because it has a higher effective nuclear charge attracting electrons in the same energy levels.

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

How many moles of al3+ ions are in 1.25 moles of al2o3