Check off each one that shows a correct conversion. Example: 1 mol Al= 6.022 x 10^23 atoms Al would be checked off. A. 2.5 mol CaCO3 = 1.51 x 10^24 molecules CaCO3

B. 2 mol Al2O3 = 101.96 g Al2O3

C. 1 mol Be3N2 = 55.06 g

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

it is reliable if two scientists recorded it