The electronic configuration of an element is 1s22s22p6. how many valence electrons does it have? 2 4 6 8

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

Which factor is likely to impact the possible number of compounds ?