The ionization potential of Be atom is more than expected because it has - (a) half filled valence p orbitals
(b) fully filled valence s orbitals
(c) both a and b

Can someone me with 3 and 4 plz. this is for masteries test.

Acalorimeter is to be calibrated: 51.203 g of water at 55.2 degree c is added to a calorimeter containing 49.783 g of water at 23.5c. after stirring and waiting for the system to equilibrate, the final temperature reached is 37.6 degree c. specific heat capacity of water (s = 4.18 j/g∙degree c). calculate the calorimeter constant. (smδt)warm water = -[(smδt)cold water + (calorimeterδtcold water)]

How is the way a mixture is combined different from how a compound is combined?