100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Summary (CAIE) Cambridge A Level Chemistry (9701) - Acids and Bases $8.30   Add to cart

Interview

Summary (CAIE) Cambridge A Level Chemistry (9701) - Acids and Bases

 16 views  0 purchase
  • Course
  • Institution
  • Book

A complete, broad and sufficiently detailed explanation of the theory of acids and bases, including: acid-base theory, the concept of pH-pOH, relative acid-base strength, acid-base reactions and how to calculate pH, identification properties and acid-base indicators , salt hydrolysis and pH calcula...

[Show more]

Preview 4 out of 42  pages

  • February 3, 2023
  • 42
  • 2022/2023
  • Interview
  • Unknown
  • Unknown
  • Secondary school
  • Unknown
  • 5
avatar-seller
Cambridge International AS and A Level Chemistry (9701)
UI CHEM 005
Study Notes & 15’s Acids and Bases Problems with Solutions




Acids and Bases

, The Acid – Base Theory

Comparison Arrhenius Bronsted-Lowry Lewis
Svante August Arrhenius Johan Nicolaus Bronsted &
Inventor & Years Thomas Martin Lowry Gilbert N. Lewis (1923)
(1886)
(1923)
Substances that when
Acid Definition The species that releases Electron pair acceptor
dissolved in water release
protons (H+) = proton donor
H+ ions
Substances that when The species that accept
Base Definition dissolved in water can protons (H+) = proton Electron pair donor
release OH- ions acceptor
Cannot recognizing the key Cannot explain an acid-base
Limitation role of the solvent in the reaction that does not
ionization of a solute involve proton transfer




The Arrhenius Acid – Base Theory


ACID BASE

 Substances that in water release H+ ions  Substances that in water release OH- ions
M(OH)x(aq) Mx+(aq) + xOH-(aq)
HxZ(aq) xH+(aq) + Zx-(aq)
 Base valence: The number of OH- ions that can
 Acid valence: The number of H+ ions that can be produced by 1 molecule of base.
be produced by 1 molecule of acid.
 The remaining base ions: Positive ions are
 The remaining acid ions: Negative ions are formed from bases after releasing OH- ions.
formed from acids after releasing H+ ions.
 Example:
 Example:
NaOH(aq) Na+(aq) + OH-(aq)
HCl(aq) H+(aq) + Cl-(aq)
Ca(OH)2(aq) Ca2+(aq) + 2OH-(aq)
H2SO4(aq) 2H+(aq) + SO42-(aq)


The Arrhenius theory does have limitations. One of the most glaring is in its treatment of the weak base
ammonia, NH3. The Arrhenius theory suggest that all bases contain OH-. Where is the OH- in NH3? To get
around this difficulty, chemists began to think of aqueous solutions of NH 3 as containing the compound
ammonium hydroxide, NH4OH, which as a weak base is partially ionized into NH4+ and OH- ions:

NH3(g) + H2O(l) NH4OH(aq)
NH4OH(aq)  NH4+(g) + OH-(aq)

, The Bronsted - Lowry Acid – Base Theory

Acid = proton (H+) donor Acid  H+ + conjugate base
Base = proton (H+) acceptor Base + H+  conjugate acid

Example:
Determine the conjugate acid-base pairs in the following reactions.



Acid HNO3 Acid H2O

Conjugate Base NO3- Conjugate Base OH-

Base H2O Base CO32-

Conjugate Acid H3O+ Conjugate Acid HCO3-



Substances that can act as both acids and bases are called amphiprotic




Hydrochloric acid is an acid because it donates a proton to water. This means that water is
acting as a Bronsted-Lowry base. The water is accepting a proton.




Water can also act as an acid. When ammonia reacts with water, it accepts a proton from
the water and becomes an NH4+ ion.

, CH3COOH(aq) + H2O(l)  CH3COO-(aq) + H3O+(aq)
Acid Base Base Acid


In reaction above, CH3COOH acts as an acid. It gives up a proton, H+, which is taken up by
H2O. Thus, H2O acts as a base. In the reverse reaction, the hydronium ion, H3O+, acts as an
acid and CH3COO- acts as a base.

When CH3COOH loses a proton, it is converted into CH3COO-. Notice that the formulas of
these two species differ by a single proton, H+. Species that differ by a single proton (H+)
constitute a conjugate acid-base pair. Within this pair, the species with the added H+ is
the acid, and the species without the H+ is the base. Thus, for the reaction above, we can
identify two conjugate acid-base pairs.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller tandhiwahyono. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $8.30. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

67096 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$8.30
  • (0)
  Add to cart