Explain how the model of atom changed between Jon Dalton's model and Niels Bohr model. (do not comment links or you will be reported)

Which position represents spring in the southern hemisphere? a) b) c) d)

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)

How many moles are in 7.2 x 10^23 carbon molecules?