Can someone please help me? I am so lost. John Dalton made the following claim: "Atoms of different elements vary in size and mass." Refer back to any of the periodic tables to support this claim with reasoning and evidence.

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?

How many molecules are in 6.0 moles of methane