Question

A 0.191g piece of solid aluminum reacts with gaseous oxygen from the atmosphere to form solid aluminum oxide. In the laboratory, a student weighs the mass of the aluminum oxide collected from this reaction as 0.199 g.The 0.191g solid aluminum is the _____.A) percent yield,

B) excess reagent,
C) limiting reagent,
D) actual yield,
E) theoretical yield

Answer 1

Answer : The correct option is, (C) limiting reagent

Explanation :

Excess reagent : It is defined as the reactants not completely used up in the reaction.

Limiting reagent : It is defined as the reactants completely used up in the reaction.

Theoretical yield : It is calculated from the amount of the limiting reagent present in the reaction.

Actual yield : It is experimentally determined.

Percent yield : It is the percent ratio of actual yield to the theoretical yield.

The balanced chemical reaction will be:

`4Al+3O_2\rightarrow 2Al_2O_3`

In this reaction, aluminium is a limiting reagent that limits the formation of product and the oxygen is an excess reagent.

Hence, the 0.191 g solid aluminum is the limiting reagent.