Chemistry Question!???!?

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How many moles of hydrogen gas can be produced when 5.0g of Zn react with 25.0 mL of 2.0 M HCl?

Please explain how you did this problem. I am having trouble!
 
answer 0.025 moles

explaination
The reaction for the equation will be as follows:

Zn + 2HCl ==> ZnCl2 + H2
given 5gm 25ml 2M

M = no of moles/ volume(in L )
=> moles = m * volume = 2 * 25/1000 = 0.05

moles of Zn given is 5/65 (i.e. mass/ molar mass)
=> 1/13 = 0.153846154

by equation Zn wud need 2/ 13 moles of HCl but we only have 0.05 moles HCl which implies HCl is limiting reagent

from equation 2 moles of HCl produces 1 mole H2

answer:
therefore 0.05 moles HCl will produce 0.05/2= 0.025 mole H2 gas
 
Well, Zn + 2HCl -> H2 + ZnCl2.
You determine the amount of moles in 5.0 g of Zn (sorry, I don't have a calculator with me) and the amount of moles of HCl and figure out if Zn or HCl is the limiting reagent. If my reaction is correct (I'm not sure it is) then the HCl is used up twice as fast a Zn.
If Zn is LR, you just transfer the moles from Zn to H2 to get the answer.
If HCl is LR, you divide the number of moles of HCl by two to get the number of moles of H2 produced.
 
Well, Zn + 2HCl -> H2 + ZnCl2.
You determine the amount of moles in 5.0 g of Zn (sorry, I don't have a calculator with me) and the amount of moles of HCl and figure out if Zn or HCl is the limiting reagent. If my reaction is correct (I'm not sure it is) then the HCl is used up twice as fast a Zn.
If Zn is LR, you just transfer the moles from Zn to H2 to get the answer.
If HCl is LR, you divide the number of moles of HCl by two to get the number of moles of H2 produced.
 
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