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

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
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
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
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?
Original post by Needhelpasap
Thank you! I got an answer of 13.96 is that right?


For a hydroxide that sounds correct
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
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
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!!!!!!!!! :biggrin:. :smile:
Original post by Needhelpasap
Thank you!!!!!!!!! :biggrin:. :smile:


image.jpg 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!!!
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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Avatar for ranz
ranz
5
is this ocr a2?


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Original post by Needhelpasap
image.jpg 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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