Question: how many unpaired valence electrons are there in an argon atom?
Answer: Argon's atomic number is 18 and there are 18 electrons in each atom. Under appropriate physical conditions one can make all the 18 electrons unpaired or 16, 14, 12, 10, 8, 6, 4, 2 electrons unpaired. in argon discharge lamp there are unpaired electrons in excited states.