Universiti Pendidikan Sultan Idris

UNIVERSITI PENDIDIKAN SULTAN IDRIS

NAMA KURSUS TEKNOLOGI MAKLUMAT DAN KOMUNIKASI DALAM KIMIA (TKU3023) TAJUK SIMULATION :

EFFECT OF SURFACE AREA ON THE RATE OF REACTION

PROGRAM PENGAJIAN PENDIDIKAN SAINS ( KIMIA ) KUMPULAN KULIAH : A

NAMA NOR MADIHAH BINTI ALI

NO. MATRIK D20081032310

SITI NOR AMIRA BINTI ZINOL

D20081032278

NAMA PENSYARAH: PN. ASMAYATI BINTI YAHYA

EFFECT OF SURFACE AREA ON THE RATE OF REACTION Teacher’s guide / Chemistry Form 5 / Spreadsheet Chemical reaction will occur when the reactant are mix together. The reaction rate or rate of reaction for a reactant or product in a particular reaction is intuitively defined as how fast a reaction takes place. For example, the oxidation of iron under the atmosphere is a slow reaction which can take many years, but the combustion of butane in a fire is a reaction that takes place in fractions of a second. The quantity of the reactant will be decrease while the quantity of product will increase within the time during the reaction occur. Therefore the rate of reaction can be determine by measure the decreasing of reactant or producing the product of the reaction. Rate of reaction = The changes of quantity of reactant Time taken The rate of reaction is increase if the time taken is short to complete the reaction. While, the rate of reaction is decrease if the rate of reaction take long time to complete the reaction. One of the factor that effect the rate of reaction is surface area .If one of the reactants is a solid, the surface area of the solid will affect how fast the reaction goes. If a solid reactant or a solid catalyst is broken down into smaller pieces the rate of reaction increases. The speed increase happens because smaller pieces of the same mass of solid have a greater surface area compared to larger pieces of the solid. Therefore, there is more chance that a reactant particle will hit the solid surface and react. The diagrams below illustrate the acid–marble chip reaction (slower => faster).

ENGAGE THE SOLUBILITY OF DIFFERENT SALT

Powder Of Salt

Thick Piece Of Salt

1. Why we put different type of salt to the water ? 2. Which salt have a greater surface area ? thick piece of salt or powder of salt? 3. Which salt will be soluble first in the water? 4. Why thick piece of salt soluble in the water slower than powder of salt ? 5. How could this happen ?

EMPOWER 1. Students plan an experiment to observe the effect of surface area on the rate of reaction

2. They are given the following apparatus : •

Gas syringe

•

Erlenmeyer Flask

•

Retort stand

•

Beaker

•

Stopper

3. They are given the following material •

Water

•

HCl

•

Thick piece of marble

•

Powder of marble

4. Students are asked to plan an experiment to show that thick piece of marble and powder of marble have different rate of reaction with acid hydrochloric 5. Students should know the effect of surface area on the rate of reaction 6. Students have to construct a hypothesis before doing the experiment 7. Help students to determine the variables involve 8.The procedures of conducting the experiment is discussed 9. When a gas formed from a marble reacting with a solution, it can be collected in a gas syringe. The time will be taken and observe the rate of reaction. 10. Log on to the website and observe the animation to answer the question http://freezeray.com/flashFiles/RatesOfReactionSurfaceArea.swf

Results:

The apparatus of experiment

The reaction between HCl and thick piece of marble

The reaction between HCL and the middle piece of marble

The reaction between HCl and the powder of marble

Questions Based on the simulation above: 1. 2. 3. 4.

What is the factor that influence the rate of reaction ? Which one of marble will produce more carbon dioxide in a short time ? Why the powder of marble will produce more carbon dioxide in a short time ? What is the effect of the rate of reaction when we use different size of the marble? 5. How does surface area effect a chemical of reaction ? 6. What is the variable we keep constant in this experiment ?

Answer : 1. The factor that influence the rate of reaction is surface area 2. Powder of marble 3. The powder of marble will produce more carbon dioxide in a short time when react with HCl because it has large surface area. So it will increase the rate of reaction. 4. When we use powder of marble the reaction rate will be increase while when we use the thick piece of marble, the reaction rate will be lower and when we use the middling piece of marble the rate of reaction also in the middle 5. If one of the reactants is a solid, the surface area of the solid will affect how fast the reaction goes. This is because the two types of molecule can only bump into each other at the liquid solid interface, i.e. on the surface of the solid. So the larger the surface area of the solid, the faster the reaction will be.Smaller particles have a bigger surface area than larger particle for the same mass of solid. There is a simple way to visualize this. So in this experiment powder of marble have a bigger surface area and thick piece of marble have smaller surface area 6. We keep constant the temperature of experiment, mass of marble that we use , concentration and volume of HCl

ENHANCE

Picture 1

Picture 2

1. From your knowledge, what is the gas needed for coal burning process occur? 2. What is the difference between both of the coal picture above? 3. Why small coal is easy to burn compared to the big one?

1. The gas needed for coal burning process occur is oxygen 2. The picture 1 shows that the size of coal is small and in picture 2, it shows that the size of coal is big. 3. The small size of coal is easy to burn because it has large surface area. In this situation, the total surface area that exposes to the air is increase. So, the reaction with oxygen ( burning process) occur fastly compared to the big size of coal which is only has small surface area that is bare to the air.