The thermite reaction was used to weld rail ties together. If 15.0 grams of aluminum were used, how many grams of ferric oxide would be required? How many grams of molten iron would forma?
2Al+Fe2O3 -> Al2O3 + 2Fe
Since the coefficients of Al and Fe are both 2, so the amount of iron formed would be in the ratio of the atomic masses, namely 55.85/26.98 (approximatelyly).