Three test tubes contain white crystalline organic solids A, B, and C, each of which melts at 149-150 degrees C. A 50-50 mixture
of A and B melts at 130-139 degrees C. A 50-50 mixture of A and C melts at 149-150 degrees C. In what range would a 50-50 mixture of B and C probably melt? What can you say about the identities of A, B, and C?
If the melting point (130 - 139 ºC) of a mixture of A and B is lower than the pure substances that is 149 - 150 ºC that means that one of these susbtances is an impurity because reduces the melting point.
If the melting point of the mixture of A and C is the same as the pure substances, we can deduce that they are the same substances, also because the melting point when a substance is pure is just 1 or 2 ºC like in this case.
So in a Mixture of B and C is going to be like the first case of the mixture among A and B, because the B substance is the impurity.
20/32=0.625 moles of sulfur 30/16 = 1.875 moles of oxygen The formula requires 1 mole of sulfur for 3 moles of oxygen which means that their is no limiting reactant as that is the ratio found thus it will react to completion forming 50 grams of product or sulfur trioxide