Which element has a complete valence electron shell?

selenium (se)
oxygen (o)
fluorine (f)
argon (ar)

What kind of simple machine is a catapult?

The bubbles in a carbonated soft drink are produced when carbonic acid decomposes to form carbon dioxide and water. in a closed system, this equilibrium exists as why does a carbonated soft drink lose carbonation when the container is left open? a.water evaporates, which favors the formation of h2co3. b.pressure decreases, which favors the formation of h2co3. c.the open container warms up, which causes more gas to escape. d.co2is removed, which favors the formation of h2co3.

Athird point charge q3 is now positioned halfway between q1 and q2. the net force on q2 now has a magnitude of f2,net = 5.861 n and points away from q1 and q3. what is the value (sign and magnitude) of the charge q3?