Question

the drawing below shows a mixture of molecules:
key
carbon hydrogen
nitrogen sulfur
oxygen chlorine
suppose the following chemical reaction can take place in this mixture:
cs₂(g)+3o₂(g)→co₂(g)+2so₂(g)
of which reactant are there the most initial moles? enter its chemical formula:
of which reactant are there the least initial moles? enter its chemical formula:
which reactant is the limiting reactant? enter its chemical formula:

Explanation:

Step1: Count reactant molecules

Count the number of $CS_2$ and $O_2$ molecules in the drawing. Assume each molecule represents 1 - mole equivalent for simplicity. There are 3 $CS_2$ molecules (each with 1 carbon and 2 sulfur atoms bonded together) and 10 $O_2$ molecules (each with 2 oxygen atoms bonded together).

Step2: Determine most - moles reactant

Since $10>3$, the reactant with the most initial moles is $O_2$.

Step3: Determine least - moles reactant

The reactant with the least initial moles is $CS_2$ as there are only 3 of its molecules compared to 10 of $O_2$ molecules.

Step4: Find limiting reactant

From the balanced chemical equation $CS_2(g)+3O_2(g)
ightarrow CO_2(g) + 2SO_2(g)$, the mole - ratio of $CS_2$ to $O_2$ is 1:3. For 3 moles of $CS_2$, we would need $3\times3 = 9$ moles of $O_2$. Since we have 10 moles of $O_2$ and 3 moles of $CS_2$, $CS_2$ will be completely consumed first. So the limiting reactant is $CS_2$.

Answer:

Of which reactant are there the most initial moles? Enter its chemical formula: $O_2$
Of which reactant are there the least initial moles? Enter its chemical formula: $CS_2$
Which reactant is the limiting reactant? Enter its chemical formula: $CS_2$