Based on these two statements, what conclusion could dalton draw about the relative masses of oxygen and hydrogen atoms? how many times more massive is an oxygen atom than a hydrogen atom?

1- He reported that seven pounds of oxygen reacted with one pound of hydrogen to form water, but accurate modern experiments give eight pounds to one.

2- by determining the relative mass we will be able to determine for example that one element has twice the mass of a second element.

3-  oxygen atoms were found to have a mass 16 times greater than the mass of hydrogen 

Well a chemical change is when substances are combined and the final product is permanent

For example ... baking a cake is a chemical change because the ingredients in the cake can't be separated as separate substances like they were in the beginning

A physical change is where the substances isn't changes, but just the appearance.

For example... origami or cutting paper is considered a physical change because even though it was cut or folded it is still paper.  

One similarity is that the physical and chemical changes are categorized under characteristic changes

-+ Hope I helped +-