As social constructions, how are race and gender the same and how do they differ?

One similarity and one difference between an element and a mixture of elements

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.

The molar mass of nickel(ni) is 58.7 g/mol. how many moles are in an 88 gram sample of nickel?