Race..Ethnicity?

Today in Chemistry class the juniors were not there and we had a small class, so we had a class discussion about topics that involved how teachers act and the way they teach and somehow we got into a discussion of how people in America view race and ethnicity as opposed to people in Europe, when asking for it on a survey or just in general. For example in Europe Spanish are considered white and in America they are Hispanic/Latino.? I personally think that when they ask for your ethnicity or race on a survey or whatever they shouldn't make it so complicated and specific.