Sales halogenas dobles

Which type of orbits are found in the principal energy level n = 2 a - s b - s, f c - s, d d - s, p e - s, p, d

Apump contains 0.5 l of air at 203 kpa. you draw back on the piston of the pump, expanding the volume until the pressure reads 50.8 kpa. what is the new volume of the air pump

What is the ph of a 0.0010 m hno3? 1.0 3.0 4.0 5.0