The number of valence electrons in an atom with an electron configuration is 1s2 2s2 2p6 3s2 3p4

Which process does not require the presence of a physical substance in order to transfer heat? air in the atmosphere is heated by the ground. this warm air then rises, and cooler air falls. this is an example of what type of process? how is conduction different from radiation?

What shape would a molecule with two bound groups and two lone pairs have?

How many moles are in 43.9 l of oxygen