How many valence electrons does phosphorus have for bonding

The boiling point of liquids is very high what does it indicate

How many moles of bromine are needed to produce 3.23 moles of potassium bromide

4.25g sample of solid ammonium nitrate dissolves in 60.0g of water in a coffee-cup calorimeter, the temperature drops from 22.0 c to 16.9 c. assume that the specific heat of the solution is the same as that of pure water. calculate delta(h) (in kj/mol nh4no3) for the solution proces.