Chemistry - Topic

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Joined: Nov 9 2021

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Nov 9 2021 09:40pm

Hiya,
Problem 1)
There's a couple steps here that you're going to want to do. The first one is to figure out what the reaction is. In this case the reaction will look somewhat like this:
Zn + HCl -> ZnCl2 + H2
Luckily, there isn't any additional stoichiometry to figure out here (the atoms on the left are they same as the atoms on the right so its balanced)
Now you will need to figure out how much HCl you have. You have a concentration (1 Mole/L) and a volume (100 cm3 = 100 ml = 0.1 L) which is all you need.
Finally, use that equation from earlier to determine how much Zn you will need to react with that much HCl (Hint: the stichometry is 1:1)
Problem 2)
You're going to be doing the same kind of process here as well. The only snag is that you have 10% HCl so you will need to take that into account. First Figure out how much HCl you need to reaction with 23g of Zn (using that stoichiometry again) then figure out what volume of 10% HCl solution will contain that amount.
Problem 3)
This is another stoichiometry question. You're going to want to figure out how much HCl you have in moles. Then figure out how much ZnCl2 it would make. Then finally divide that amount of ZnCl2 by the volume of your solution (the same volume of HCl solution given in the question)

As an overarching theme that you should take from these types of problems is that figuring out the stoichiometry of the reaction and figuring out how many moles of the things you care about there are will almost always make the problem much easier to solve. Hope this all help!