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chem calculation question help watch

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    i've tried searching everywhere for an example of this type of question but i can't find it.

    1. Calculate the volume of hydrogen producted in the reaction of excess zinc with 500cm3 of 1 mol/dm3 hydrochloric acid at 20 degrees.
    {one mole of any gas occupies 24,000cm3 at room temp and pressure}

    please help!
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    Is it not a combination of formulas so eventually you use the formula triangle for gas volume?
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    (Original post by Crammyandcrabby)
    i've tried searching everywhere for an example of this type of question but i can't find it.

    1. Calculate the volume of hydrogen producted in the reaction of excess zinc with 500cm3 of 1 mol/dm3 hydrochloric acid at 20 degrees.
    {one mole of any gas occupies 24,000cm3 at room temp and pressure}

    please help!
    First use n=vc to calculate the number of moles of HCL
    (Remember to convert cm^3 into dm^3)

    Then write the word equation and work out the ratio: I got 2:1 and calculate the number of moles of zinc

    Then use the equation n=v/24,000 to work out the number of moles on Zinc

    Hope this helps!
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    (Original post by JulieWaters)
    First use n=vc to calculate the number of moles of HCL
    (Remember to convert cm^3 into dm^3)

    Then write the word equation and work out the ratio: I got 2:1 and calculate the number of moles of zinc

    Then use the equation n=v/24,000 to work out the number of moles on Zinc

    Hope this helps!
    Thanks a lot! This really helped! I understood everything you said except the n=vc, what did you mean by this?
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    (Original post by Crammyandcrabby)
    Thanks a lot! This really helped! I understood everything you said except the n=vc, what did you mean by this?
    He meant: Concentration = No of moles / Volume

    Therefore: No of moles = Volume * Concentration
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    (Original post by SaadKaleem)
    He meant: Concentration = No of moles / Volume

    Therefore: No of moles = Volume * Concentration
    Thanks a lot! Also do you know at the end of his statement he said to work out an equation to get the volume of zinc....did you know if he meant get the volume of hydrogen?
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    (Original post by Crammyandcrabby)
    Thanks a lot! Also do you know at the end of his statement he said to work out an equation to get the volume of zinc....did you know if he meant get the volume of hydrogen?
    Probably meant Hydrogen, try it for yourself, write down the equation (balanced) and find the mol of HCl and compare with the mol of H2 and find it's volume.
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    (Original post by Crammyandcrabby)
    Thanks a lot! Also do you know at the end of his statement he said to work out an equation to get the volume of zinc....did you know if he meant get the volume of hydrogen?
    yes I did haha!!
 
 
 
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