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Please please help!!! Need help with chemistry question:) watch

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    KOH CONC is 0.032 Volume added is 40cm3
    Propanoic acid conc is 0.024 volume added is 25cm3

    kW is 1.0x10-14

    Calculate the pH
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    (Original post by Needhelpasap)
    KOH CONC is 0.032 Volume added is 40cm3
    Propanoic acid conc is 0.024 volume added is 25cm3

    kW is 1.0x10-14

    Calculate the pH
    By the sounds of it, it looks like a stoichiometry style question. Im guessing form an equation with the two chemicals, find the conc of water, and then use the kw equation to find OH ions and do the log of that
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    (Original post by Needhelpasap)
    KOH CONC is 0.032 Volume added is 40cm3
    Propanoic acid conc is 0.024 volume added is 25cm3

    kW is 1.0x10-14

    Calculate the pH

    Sorry ignore my last answer. Okay formulate an equation find the initial number of moles and do stoichiometry to find the moles of the product. Then use n=cxv but the volume is the two volumes added together as the two chemicals have been mixed. Then you will know OH ions then find H ions from kW and do LOg for ph
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    (Original post by hasan6091)
    Sorry ignore my last answer. Okay formulate an equation find the initial number of moles and do stoichiometry to find the moles of the product. Then use n=cxv but the volume is the two volumes added together as the two chemicals have been mixed. Then you will know OH ions then find H ions from kW and do LOg for ph
    Thank you! I got an answer of 13.96 is that right?
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    (Original post by Needhelpasap)
    Thank you! I got an answer of 13.96 is that right?
    For a hydroxide that sounds correct
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    Thank you!
    How how would I answer this question -

    The yeild is 78%
    Mass of sodium P I's 2.5 tonnes
    The molar mass iis 116
    The molar mass of aspirin is 180 calculate the mass of asprin produced



    (Original post by hasan6091)
    For a hydroxide that sounds correct
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    (Original post by Needhelpasap)
    Thank you!
    How how would I answer this question -

    The yeild is 78%
    Mass of sodium P I's 2.5 tonnes
    The molar mass iis 116
    The molar mass of aspirin is 180 calculate the mass of asprin produced
    Calculate moles of Na im guessing its 1:1 ratio, then find the mass of aspring and find 78 percent of the value
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    (Original post by hasan6091)
    Calculate moles of Na im guessing its 1:1 ratio, then find the mass of aspring and find 78 percent of the value
    Thank you!!!!!!!!! .
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    (Original post by Needhelpasap)
    Thank you!!!!!!!!! .
    Name:  image.jpg
Views: 37
Size:  101.1 KB I've not got the marks heme for this question. Can u please tell me if my answers are right?

    For Ii. I got -201.7
    For iii I got -563.7




    Thank you!!!
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    (Original post by hasan6091)
    Calculate moles of Na im guessing its 1:1 ratio, then find the mass of aspring and find 78 percent of the value
    Click image for larger version. Name: image.jpg Views: 0 Size: 101.1 KB ID: 495021 I've not got the marks heme for this question. Can u please tell me if my answers are right?For Ii. I got -201.7 For iii I got -563.7Thank you!!!
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    is this ocr a2?


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    (Original post by Needhelpasap)
    Name:  image.jpg
Views: 37
Size:  101.1 KB I've not got the marks heme for this question. Can u please tell me if my answers are right?

    For Ii. I got -201.7
    For iii I got -563.7





    Thank you!!!
    Formation is products - reactants
    Entropy should be in a data sheet
 
 
 
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