Gold is found in nature state but not iron whyon​

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)

The volume of an unknown substance in a sealed glass jar is 50 milliliters. the volume of the jar is 200 milliliters. which state of matter could the substance be?

The sum of the oxidation numbers in a neutral compound is always