100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Revision Powerpoint on Equilibrium OCR Chemistry A level 2015 $3.97
Add to cart
Quickly navigate to
Preview
  2.  
  3. OCR
  4.  
  5. Chemistry
  6.  
  7. A2 Unit F325 - Equilibria, Energetics and Elements

Other

Revision Powerpoint on Equilibrium OCR Chemistry A level 2015
 0 purchase
  • Course
  • A2 Unit F325 - Equilibria, Energetics and Elements
  • Institution
  • OCR

Powerpoint giving in depth information of the topic. Can be printed with 2-4 slides on a page and cut out to form a mini revision booklet. Very colourful. 12 slides

Preview 3 out of 12  pages

Document information

  • May 23, 2017
  • 12
  • 2016/2017
  • Other
  • Unknown

Subjects

  • chemistry
  • ocr
  • ocr a level 2015
  • equilibrium

Written for

  • A/AS Level
  • OCR
  • Chemistry
  • A2 Unit F325 - Equilibria, Energetics and Elements
All documents for this subject (10)

Seller

avatar-seller
megancoleman

Reviews received

Content preview

Equilibrium

, The equilibrium constant Kc
The equilibrium law tells us the relative proportions of
reactants and products when a reaction is at equilibrium.
aA+bB ⇄ cC+dD The square brackets show
Kc= [C] ͨ [D] ͩ [products] . concentration in moldm¯³

[reactants]
[A] ͣ [B]ᵇ The indices are the numbers in front of
Equilibrium constant each substance in the chemical equation
C shows that its in terms of
concentration
 If Kc has a value of 1 then the
Examples position of equilibrium is
H₂ (g) +I₂(g) ⇄ 2HI(g) halfway between the reactants
and products
The equilibrium constants are  If Kc>1 then the reaction is
H₂ 0.140 moldm¯³ product favoured so there are
HI 0.320 moldm¯³ more products at equilibrium
I₂ 0.0400 moldm¯³  If Kc<1 then the reaction is
Kc= [HI(g)]² Kc= [0.320(g)]² .=18.3 reactant favoured so there are
[H₂(g)][I₂(g)] [0.14(g)][0.04(g)] more reactants at equilibrium

, Example from experimental results
N₂(g) + 3H₂(g)  2NH₃(g)
2.5mol of N₂ and 6.2 mol of H₂ were placed in a 5dm³ container & were left
to reach equilibrium. 2 mol of NH₃ was measured at equilibrium
Calculate the Kc of this reaction
Step 1: work out the equilibrium amounts of all equilibrium species using
MICE (Eq)
ratio 1 3 2 if this was a
Molecules N₂ H₂ NH₃ heterozygous equilibrium
only (g) & (aq)would be
Initial moles 2.5 6.2 0 included in working out
Change in moles -1.0 -3.0 +2.0
If value of v is unknown
Equilibrium moles 1.5 3.2 2.0
just use ‘v’ as this will
Equilibrium concentration 1.5/5=0.3 3.2/5=0.64 20/5=0.4 cancel out in the Kc
(c=n/v) expression


Step 2: write expression for Kc
Kc= [NH₃]² units= [moldm¯³]² .
[N₂][H₂]³ [moldm¯³] [moldm¯³]³
Kc= 0.4² .
0.3 x 0.64³ units=mol⁻²dm⁶
= 2.03
2.03>1 so product favoured

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 megancoleman. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $3.97. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

66184 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 15 years now

Start selling
$3.97
  • (0)
Add to cart
Added