Question

How many moles of NaCl could be made by combining 20,000 moles of Na with 2 moles of Cl?
a.
20,000 moles NaCl
c.
2 moles NaCl
b.
1 mole NaCl
d.
None of the above

Answer 1

i guess no luck :(

Answer 2

:/

Answer 3

Let's look at the balanced chemical equation for this reaction:

\[Na _{(s)} + Cl_{(s)} \rightarrow NaCl _{(s)}\]

I'm assuming that the chlorine you are referring to here is not chlorine gas (Cl2), as this would change the above chemical equation. So, the above equation describes how a single atom of solid sodium reacts with a single atom of chlorine (in this case we'll say it's a solid, although it doesn't really matter in terms of this question) to form one molecule of the solid ionic compound sodium chloride, NaCl (table salt). The equation is balanced, meaning that the same number of all atoms are in the reactants and the formed product, as can be seen above (i.e. we do not have to add any coefficients).

So, with this balanced chemical equation we can say that:
"For every 1 mole of Na I react with every 1 mole of Cl, I will get 1 mole of the product, NaCl."

We know we have 20,000 moles of Na and 2 moles of Cl. Let's just think about what will happen here, based on what we said above. We only have 2 moles of Cl, and it will happily react with 2 moles of the Na to form 2 moles of NaCl. After that, the Cl is gone, we can't get the reactant back as it has been entirely used up in forming the maximum amount of the product it can form. This means that we still have a load of Na atoms left over with nothing to react with to form sodium chloride. So,

- We say that the Na is IN EXCESS (UNUSED REACTANT), and
- That the Cl is THE LIMITING REACTANT OR LIMITING REAGENT, AS THE AMOUNT OF THIS WE HAVE DETERMINES HOW MUCH OF THE PRODUCT IS ACTUALLY FORMED, BASED ON WHAT WE ARE FORMING.
Hope that helps! :)

Answer 4

wow you typed alot,hope i didnt take much of your time, thank you. :)

Answer 5

No problem at all @belias2111 , hope that clears it up for you! :)

Answer 6

Thank you @belias2111 :)