Which are physical changes? Select all that apply.
cleaning stains with bleach
curling hair with rollers
cutting cheese with knife
cooking egg whites in skillet

Which is the layer underground where all empty spaces are filled with a combination of air and water ?

What are the chemical names of these compounds? ke: mg3n2: reset next

Given the following at 25c calculate delta hf for hcn (g) at 25c. 2nh3 (g) +3o2 (g) + 2ch4 (g) > 2hcn (g) + 6h2o (g) delta h rxn= -870.8 kj. delta hf=-80.3 kj/mol for nh3 (g), -74.6 kj/mol for ch4, and -241.8 kj/mol for h2o (g)