100% de satisfacción garantizada Inmediatamente disponible después del pago Tanto en línea como en PDF No estas atado a nada
logo-home
chem1012/1013A:complete notes and steps-8DEC2021 $4.81   Añadir al carrito

Examen

chem1012/1013A:complete notes and steps-8DEC2021

 18 vistas  1 veces vendidas
  • Grado
  • Institución
  • Book

Often students are faced with a blockage in many questions in semester 2 due to the inaccessibility of the set of instructions which ultimately make it easy to comprehend questions. Chemistry is often disguised as a subject that requires much understanding and a lot of memorizing, yet this is not t...

[Mostrar más]

Vista previa 3 fuera de 29  páginas

  • 7 de diciembre de 2021
  • 29
  • 2021/2022
  • Examen
  • Preguntas y respuestas
avatar-seller
CHEM 1012A/1013A
By Amatullah Chiosa




Often students are faced with a blockage in many questions in semester 2 due to the
inaccessibility of the set of instructions which ultimately make it easy to comprehend questions.
Chemistry is often disguised as a subject that requires much understanding and a lot of
memorizing, yet this is not the case for many of the top achievers. Top achievers compress their
understanding into a simple set of instructions that they use. Fortunately, this set of instructions
are found and explained in this document.




CONCEPTS COVERED
Chemical kinetics
Chemical equilibrium
Acids and base equilibrium
Aspects of aqueous equilibria
Thermochemistry

, Chemical kinetics
Chemical kinetics- ‘measurement of how quickly reaction occur.’1
Rate of reaction is the change in concentration per unit time.
[𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑐𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑖𝑜𝑛] 𝛥𝑚𝑜𝑙𝑎𝑟𝑖𝑡𝑦
Average rate= 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑡𝑖𝑚𝑒
= 𝛥𝑡 = M.s-1

Rate law shows the relationship between rate of reaction and concentrations of the reactants.
For the chemical reaction: aA+bB⇌cC+dD
rate law=k[A]m[B]n.
k is the rate constant
m, n are the numbers indicating the reaction order.
The reaction order indicates the relationship between the concentration of species and the rate of
the reaction.

Finding The Reaction Order:
CASE 1:
If the overall reaction order is not given. Use the coefficients of the reactants.
• When rate of reaction is proportional to the concentration of a substance then it is
a first order reaction, meaning power of A is 1. (a unimolecular process- one mol-
ecule involved)
• When rate of reaction is proportional to the A2, then it is a second order reaction.
(a bimolecular process-two molecules involved)
• When rate of reaction is independent of the concentration of A, then the reaction
is a zero-order reaction.
E.g., aA+bB ⇌cC
Rate law= k[A]a[B]b
CASE 2:
If overall reaction order is given.
Overall reaction order= sum of the individual reaction orders.

E.g., aA ⇌Bb + cC
Overall reaction order=2
Rate law=k[A]2
CASE 3: More than 1 rate of reaction is given (this may be in the form of a table).

1
Chemistry: the central science, Brown et al. (Brown et al., no date)

, Then follow this three-step system to find the reaction order which is the power of the
concentration of the reactants
Step 1: if there is more than one reactant, look for the two rows where only one reactant
concentration changes.

e.g.
aA+bB ⇌ 𝑐C

[A] [B] Rate of reaction
0.1 0.3 1.64x10-4
0.1 0.6 1.78x10-4
0.21 0.3 3.2x10-4

Step 2: substitute into this formula
𝑟𝑎𝑡𝑒2 𝑎 𝑏
[0.6] 𝑎 𝑏 [0.6] −4

𝑟𝑎𝑡𝑒1
==𝐾[0.1]
𝑘[0.1]𝑎 [0.3]𝑏
=𝐾[0.1]
𝑘[0.1]𝑎 [0.3]𝑏
=1.78𝑥10
1.64𝑥10−4
⟹ 1.085=2b ⟹ b=log2[1.085]⟹ b= 0.12


Step 3: repeat above process to find a.
𝑟𝑎𝑡𝑒3 𝐾[𝐴]𝑎 [B]𝑏 3.2𝑥10−4 𝐾[0.21]𝑎 [0.3]𝑏
= ⟹ = ⟹ 1.95=2.1b ⟹ b=log2.1[1.95] ⟹ a= 0.9
𝑟𝑎𝑡𝑒1 𝑘[𝐴]𝑎 [𝐵]𝑏 1.64𝑥10−4 𝑘[0.1]𝑎 [0.3]𝑏

Overall reaction order=0.12+0.9=1.02


.

Half-Life: First Order Reaction
The time needed for a reaction to reach half of its original concentration. t1/2 is independ-
ent of concentration.
0.693
t1/2= 𝑘



Collision Theory: Temperature and Rates
Collision literally means for two objects to crash or hit against each other. For this to happen
well enough to cause a reaction; enough molecules must collide at the right kinetic energy. The
more the collisions, the faster the rate. As the kinetic energy increases, so does the speed at
which it occurs, and the rate consequently increases.
In simple terms: average kinetic energy= temperature ∝ reaction rate

Los beneficios de comprar resúmenes en Stuvia estan en línea:

Garantiza la calidad de los comentarios

Garantiza la calidad de los comentarios

Compradores de Stuvia evaluaron más de 700.000 resúmenes. Así estas seguro que compras los mejores documentos!

Compra fácil y rápido

Compra fácil y rápido

Puedes pagar rápidamente y en una vez con iDeal, tarjeta de crédito o con tu crédito de Stuvia. Sin tener que hacerte miembro.

Enfócate en lo más importante

Enfócate en lo más importante

Tus compañeros escriben los resúmenes. Por eso tienes la seguridad que tienes un resumen actual y confiable. Así llegas a la conclusión rapidamente!

Preguntas frecuentes

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.

100% de satisfacción garantizada: ¿Cómo funciona?

Nuestra garantía de satisfacción le asegura que siempre encontrará un documento de estudio a tu medida. Tu rellenas un formulario y nuestro equipo de atención al cliente se encarga del resto.

Who am I buying this summary from?

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

Will I be stuck with a subscription?

No, you only buy this summary for $4.81. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

45,681 summaries were sold in the last 30 days

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

Empieza a vender

Vistos recientemente


$4.81  1x  vendido
  • (0)
  Añadir