Tuesday, 19 July 2016

Risk Assessment

Risk Assessment  
Step 1:
Identify the hazard
CSIS User code
(for chemicals only)
Step 2:
Strategies to minimise the hazard
Step 3:
Assessment of risk (see table below)
Step 4:
What if something goes wrong?
Step 5:
Packing up
Using a knife to cut the apple slices may result in cuts to the fingers.
Make sure you have an adult around and don’t use an extremely sharp knife
Tell an adult immediately and do not freak out or panic as you will be putting other people in danger.
Make sure that the knife has no blood on it and make sure that it is not in reach of younger children.
Lemon juice getting in your eyes
Be careful when squeezing juice and wear safety goggles
Tell an adult immediately and apply water to the sting
Make sure there is no left over lemon juice on the counter
Mandatory precautions: Covered shoes, safety glasses, hair exceeding shoulder length tied back.
This is my risk assessment from the end of last term that went along with the SRP proposal that is the previous blog.

Date: ……….…           Student Signature: ……………………………………….
How do you assess the risk? For each hazard identified in Step 1, answer A then answer B. Then add A and B together to determine Risk and Action required
What is the potential impact or consequence of the hazard?
What is the likelihood of the event happening?
Add the numbers in columns A and B together
How to asses the risk
First Aid required with little or no lost time
1 = LOW
It could happen but only rarely
1 – 2 = LOW RISK
Proceed with caution
Medical treatment required, some lost time
It could occasionally happen
Consult with teacher
Medical treatment required, extended lost time
3 = HIGH
It could frequently happen
5 – 6 = HIGH
Reassess the need to perform practical/ consult with teacher

SRP Proposal

Here is my SRP proposal which I completed last term. I received 11/12 for it and the area where I lost marks was the method because it was not clear as to how I would measure the amount of oxidized areas on the apple. So, to resolve this issue, I diced the apples into small cubes and put 100 of them in each of the bowls so that it is easy to determine which brown squares had oxidized.

To discover if apples will oxidize when lemon juice, extra virgin olive oil, vinegar and tap water has been spread onto the surface of the apple slices.

The lemon juice will have the biggest impact on preventing the apple to turn brown.

Equipment list (including quantities, brands, sizes)
  1. 3x lemon
  2. 100 mL of tap water
  3. 100 mL of  extra virgin olive oil
  4. 100 mL of vinegar
  5. 1x sieve
  6. 1x pair of tongs
  7. 4x bowls (plastic or glass)
  8. 1x foil sheet
  9. 1x stopwatch or timer

Risk Assessment
Use recommended template on Enable (print and attach to this proposal)
  1. All materials were collected and put on the counter table
  2. The 4 bowls were spread out across the table
  3. The lemon was cut into 2cm slices
  4. 100 mL of water was poured in a bowl
  5. 100 mL of Extra Virgin Olive Oil was poured in a bowl
  6. 100mL of Vinegar was poured in a bowl
  7. The apple was cut into 2cm slices  
  8. The stopwatch was set to 3 minutes
  9. At the same time, 3 apple slices were dropped into each bowl and the timer was started
  10. After 3 minutes was up, using the tongs, the apple slices were removed from the bowl and placed on foil
  11. The timer was then reset to 180 minutes and the apple slices were left in the shade and the timer was started
  12. The apple slices were observed and the amount of brown spots on the apple was recorded

Outline of variables
  • The type of substances used to cover the apples - vinegar, lemon juice, tap water and olive oil.
  • The reaction of oxidation. How brown the apples become overtime.
  • Type of apple
  • Size of apple slice
  • Amount of liquid substances being exact
  • Environment (if some sun is exposed on the apple slice)
  • Set time or amount of time exposed

Friday, 8 July 2016


Today I am conducting the experiment with the extra variable which is the plain apple.

Extra Variable

at the moment, the substances I have used are 
  1. Lemon juice 
  2. extra Virgin olive oil
  3. White Vinegar
  4. Water 
I have decided to add another one which is just plain so there is nothing on the apple and its easy to compare.

Tuesday, 5 July 2016

results from trial experimant

The results from the trial experiment were exactly what I expected. These are the results from the trial experiment from the substance that worked the most and prevented oxidisation to the substance that did not work in prevention the oxidising.

  1. lemon juice 
  2. olive oil
  3. white vinegar 
  4. tap water
here are some photos as to what it looked like: 
apples in lemon juice after an hour - lemon juice worked best
apples in water after an hour - water was the worst substance in preventing oxidisation 
All of the apple samples with each of their different substance after 30 minutes 

Change to Procedure

In my previous blog, when I was talking about the problems and the resolutions I had come up with to those problems, this is one of the things that I stated:

  1. problem - as soon as the apple is cut it has started to oxidize so as soon as they are cut into slices the timer has to start because they are exposed to the oxygen solution - an extra 1 minute has been added to the method where the apples are cut and dices in the apple dicer and then they would be put into the different solutions.  
I said that a minute would be added to the procedure to cut and dice the apples and excreta. I have decided to change it from 1 minute to 3 minutes so that there is time to do everything accurately.

Sunday, 3 July 2016

Trial SRP

I have conducted the trial experiment for my SRP. The science and theory behind the experiment worked but there were a few issues that came across in the trial SRP. Here are the issues and the solutions I have come up with to prevent an inaccurate experiment:

  1. problem - sun being exposed on some of the apple cubes. solution - all of the bowls with the apple slices were moved into the pantry where there were doors so the same amount of light was exposed onto all of the different bowls. 
  2. problem - finding out how much of the apples had turned brown solution - originally, my plan was to cut the apples into slices but then it became clear to me that the strategy used to find out how much of the apple slice had oxidized was hard as there was no exact proportion and it would be very hard to get an accurate result. So, I used an apple dicer that dices the apples into small cubes. I would then pick out 100 of the small cubes and that way it is easier to see how many apple cubes have oxidized. This is a good strategy because you can then find out as a percentage, decimal and fraction how many of the cubes have oxidized in each of the substances. 
  3. problem - as soon as the apple is cut it has started to oxidize so as soon as they are cut into slices the timer has to start because they are exposed to the oxygen solution - an extra 1 minute has been added to the method where the apples are cut and dices in the apple dicer and then they would be put into the different solutions.  

  1. (this link is a PICTURE of the apple dicer and what it looks like) http://www.shopandrecharge.com/ideal-home-nicer-dicer-plus-plastic-potato-apple-banana-carrot-grater-and-slicer-for-rs-435-at-flipkart-com/