Answer:
Iron, according to:
Step-by-step explanation:
Hi there!
In this case, according to the law of conservation of mass, which states that matter cannot be neither created nor destroyed, it is possible for us to figure out the missing element in the reaction by taking into account this is a single displacement reaction in which Al goes with NO3 to produce the Al(NO3)3, and therefore the other element would be iron (Fe) as can be seen on the following chemical reaction:
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