Molar concentration of acids & bases

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Alondra
Posts: 36
Joined: Tue Feb 26, 2019 12:15 am

Molar concentration of acids & bases

Postby Alondra » Sun Jan 19, 2020 6:56 pm

If you're asked about the molar concentration of H30+ or OH- would you leave the answer as just the concentration with units mol.L^-1 or do you have to define this concentration as logarithms (pH=-log[H30+] and pOH-log[OH-])?

Rodrigo2J
Posts: 87
Joined: Sat Jul 20, 2019 12:16 am

Re: Molar concentration of acids & bases

Postby Rodrigo2J » Sun Jan 19, 2020 6:58 pm

if it asks for molar concentration then you just need to leave your answer in terms of molarity or (mol/L). The question should ask you for pH or pOH if they want that specific answer.

JonathanS 1H
Posts: 86
Joined: Thu Jul 11, 2019 12:17 am

Re: Molar concentration of acids & bases

Postby JonathanS 1H » Sun Jan 19, 2020 6:59 pm

If you are asked specifically for molar concentrations, you would give the moles/Liter rather than the pH or pOH.

Christine Honda 2I
Posts: 102
Joined: Sat Sep 14, 2019 12:17 am

Re: Molar concentration of acids & bases

Postby Christine Honda 2I » Sun Jan 19, 2020 7:00 pm

If it asks for molar concentrations I believe it is asking for mol/L. pH or pOH will be asked for specifically.

TimVintsDis4L
Posts: 81
Joined: Sat Aug 17, 2019 12:17 am

Re: Molar concentration of acids & bases

Postby TimVintsDis4L » Sun Jan 19, 2020 7:01 pm

Just remember that pH = -log[H30+] and pOH= - log [OH-] so try not to get them confused. If only one is given, then subtract the pH from 14 to get the other.

Daria MacAuslan 1H
Posts: 35
Joined: Sat Aug 17, 2019 12:16 am

Re: Molar concentration of acids & bases

Postby Daria MacAuslan 1H » Sun Jan 19, 2020 7:14 pm

If you are asked for the molar concentration, answer in mols/L, rather than pH or pOH. If you are asked for either of those, though, then you would need to take the negative log of the molar concentration and answer in that way.

Rosa Munoz 2E
Posts: 89
Joined: Wed Sep 18, 2019 12:21 am

Re: Molar concentration of acids & bases

Postby Rosa Munoz 2E » Sun Jan 19, 2020 7:15 pm

molar concentration deals with molarity

Eesha Chattopadhyay 2K
Posts: 89
Joined: Fri Aug 09, 2019 12:16 am

Re: Molar concentration of acids & bases

Postby Eesha Chattopadhyay 2K » Sun Jan 19, 2020 7:17 pm

It will ask specifically for pH or pOH if that's what they want. Otherwise, just give in the units of what they're asking for.

preyasikumar_2L
Posts: 86
Joined: Fri Aug 09, 2019 12:17 am

Re: Molar concentration of acids & bases

Postby preyasikumar_2L » Sun Jan 19, 2020 8:27 pm

If you're asked for the molar concentration of H3O+ or OH- you can leave your answer in terms of mol/L. Only when they ask for the pH or pOH do you have to think about taking the logarithms of those values.


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