What is the pressure (in atm) of a gas trapped in a balloon along with water vapor at 30 degrees Celcius if the atmospheric pressure is 1.005 atm? Show all your calculation (Hint: Review Dalton's Law of partial pressures).

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

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