If you have ideas, suggestions and questions for the moderators and administrators about the forum, post them here.

## 252 topics in this forum

• 89

• 0

• 6

• 39

• 12

• 3

• 3

• 1

• 3

• 1

• 1

• 9

• 3

• 1

• 4

• 0

• 1

• 0

• 1

• 4

• 0

• 2

• 8

• 6

• 2

• 4

• 0

• 1

• 0

• 0

• ### Posts

• You may be surprised just how many posts we get on applying to York Regional IB schools. There are a lot more. Use the search bar at the top right of this page. (It seems that whenever people mention the name of IB school they are applying to, it's always Bayview or something). It seems that you are well prepared for math. They shouldn't test you on grade 9 material. If you have been reading on a regular or semi-regular basis then you should be fine for reading.
• The rate law is always empirically derived, and is independent of the number of reactants present. You can have only one reactant in a higher ordered reaction, or multiple reactants but zeroth or first ordered. In particular, Arrhenius equation only describes how temperature changes the rate constant, and it does not care about the order of reaction the rate constant is for. You should read more about how to derive rate laws for reactions of multiple steps, specifically regarding the equilibrium assumption and the pseudo steady state assumption. Maybe also review limiting reagents. Answer to Q1. The formula is for the reaction Fluorophore* -------> Fluorophore + Light. But you can assume that that rate is reflective of the original phenyl oxalate ester / H2O2 reaction. You should clearly justify this assumption. Answer to Q2. The short answer is yes. The long answer is that it doesn't matter. Digital probes rarely directly measures the quantity it outputs. Usually some conversion/calculation is done by the probe from an original measurement in resistance or pressure change to the desired quantity, such as illumination. It does not matter whether illumination is the same as illuminance; it's important that illumination (or whatever the output reading is) is proportional to the concentration of the fluorophore, or another chemical species of interest.
• Hello, so the entrance exams for some programs are coming around this November, and I'm doing a few exams, but one that stands out to me is the entrance exam for Saint Roberts CHS pre IB. I know that they don't test French, but for the math, is it around grade 8 curriculum level or is it more like grade 9 curriculum math? Also, for the reading comprehension part, how can I prepare? I've been doing Gauss math contests, grade 7 and 8, and usually I can get all Part A and Part B questions right ; however, Part C questions tend to stump me, usually I get 2 or 3 of the Part C questions right, but once in a blue moon I can get the last 2? My reading comprehension preparation has literally just been me finding online resources, I've been trying to read higher grade passages.  I've also heard that apparently the math is kind of like the CAT test math? Is that true? Anyways, thank you!
• For my IA, I'm trying to find the activation energy of a glowstick reaction (phenyl oxalate ester + hydrogen peroxide). Using the Arrhenius equation and the integrated rate laws, and using this link as a guide (https://www.westminster.edu/about/community/sim/pdf/SLIGHTSTICKKINETICS_001.pdf), I was able to come up to a certain point. I have two questions.

In the link, I see that it used first-order kinetics in order to create an equation that relates rate of reaction to temperature (with activation energy/R being the slope). However, as far as I know, first-order kinetics only applies to chemical reactions with one reactant. I then looked at another source, which breaks up the chemiluminescence process into several steps, as shown by this source (http://cartwright.chem.ox.ac.uk/tlab/experiments/X3_kinetics.pdf). Was the formula in the first link regarding the decomposition of the peroxyacid ester?

My second question is that in the first document, it creates an equation that shows a linear relationship between rate of reaction and illumination. Would illumination be illuminance which could be measured in lux?
• Google sites is totally fine. Also, you're most definitely allowed to use click and drag web builders @kw0573. I used Wix and wrote very little HTML and still got a high 6 for my IA. The key lies more with the documentation than the actual product, I've found.

×