Question

Consider the following statements.
1. If all the reactants are not taken in their stoichiometric ratio, then at least one reactant will be left behind.
2. 2 moles of ${H_2}$(g) and 3 moles of ${O_2}$(g) produce 2 moles of water.
3. If equal weights of carbon and oxygen are taken to produce $C{O_2}$, then ${O_2}$ is limiting reagent.
The above statements 1, 2, 3 respectively are (T = True, F = False ) :
a.) T T T
b.) F T F
c.) F F F
d.) T F T

Answer 1

Hint: This question is all about limiting reagent. The Limiting reagent is the reactant that is present in lower quantity and on which the rate of the reaction depends. The amount of limiting reagent will decide the amount of product formed.

Complete step by step answer:
This question is all about limiting reagent. First, let us see what is limiting reagent.
The Limiting reagent is the reactant that is present in lower quantity and on which the rate of the reaction depends. Now, let us see the statements. The first statement says that if all the reactants are not taken in their stoichiometric ratio, then at least one reactant will be left behind. This statement is true because if reactants are not in a stoichiometric ratio, then the limiting reagent will be consumed fully leading to a stop of reaction and leaving behind the other reactant. The second statement says that 2 moles of ${H_2}$(g) and 3 moles of ${O_2}$(g) produce 2 moles of water. Let us write the reaction for this as -
$2{H_2} + 3{O_2} \to 2{H_2}O$
This statement is also true because hydrogen being the limiting reagent here stops the reaction after formation of two moles of water. The oxygen is left in excess.
The third statement says that if equal weights of carbon and oxygen are taken to produce $C{O_2}$, then ${O_2}$ is limiting reagent.
Let us write the reaction as -
$C + {O_2} \to C{O_2}$
The oxygen is the limiting reagent means the reaction depends upon the amount of oxygen. This is also true because if equal weights of carbon and oxygen are present then as the weight of oxygen is more than weight of carbon. So, moles of carbon present will be more than that of oxygen. This means a lesser amount of oxygen is present. So, it will be the limiting reagent. Thus, all the statements are true.

So, the option a.) is the correct answer.

Note: It must be noted that the number of moles of a component can be calculated by dividing the given mass with the molar mass. If the given mass is equal as in statement 3; but the molar mass of carbon is 12 while that of oxygen is 16. So, the number of moles of carbon will be more than that of oxygen.