My Life in the Past Thirty Days

During the past thirty days or so, I went through what was the busiest and most work-loaded time of my life. I had to complete two reading journals, write and present a speech, create a 25-page picture book about Macbeth, prepare an application for a summer camp, finish building my bridge for physics class, write my English ISP essay, and... you get the idea. I also had to constantly review school materials at home because there was an unusually large amount of tests. As a result, I had almost no chance to take a break and relax myself.

Perhaps this was why I got sick on December 8th (I think?). So sick that I couldn't concentrate, couldn't think properly, couldn't even eat without vomiting afterwards! Consequently, I had to stay at home to recover, and to go to a doctor to do some checkups. Fortunately, I got better after two days, and the doctor couldn't find anything particularly wrong with me.

So, I resumed my school life, gradually caught up with my school work, and miraculously completed all assignments in the next two weeks. Unfortunately, just as I was about to celebrate the beginning of the winter break, I started sneezing and coughing! And as if these are not bothersome enough, I also had major nosebleeds for four days in a row.

Evidently, my life in the past thirty days hasn't been very pleasant or comfortable. I had a ton of school work, as well as many physical/health problems. However, now that it is the winter break, I am sure I can get myself back together, and have the next thirty days of my life completely different from the last thirty days of my life. 

Busy, Busy, Busy

For the next few weeks or so, I will be extremely busy— busier than I ever was. I will have to complete four to six tasks each day, and each of them will take at least half an hour (and as much as 2-3 hours). So starting tomorrow, I must not even waste a minute on television, Internet-surfing, or games. I also have to make sure that I am constantly thinking about my projects so that they will not have poor qualities. Otherwise, my marks will suffer and my average will be even lower than it is now.

Rant: My English teacher is driving me crazy! Five *big* assignments in 20 days!? How's that giving us "ample amount of time" for each assignment?

Chemical Equilibrium #4: Manipulating the Equilibrium Constant (keq)

When calculating the keq of the reverse reaction:

When multiplying the entire equation by a number:

When adding several equations together:

Chemical Equilibrium #3: Equilibrium Constants

In a closed chemical system at constant temperature, there's a constant (k_eq) that defines the relationships between the concentrations of products and reactants.

K_eq= (concentration of each product raised to a power of the coefficient of the corresponding product)÷ (concentration of each reactant raised to the coefficient of the corresponding reactant).

To make it more clear,

(where the lower case letters are the coefficients)

What k_eq tells:
Since k_eq is products over reactants, the larger it is, we know that the more products there are in the equilibrium (and vice versa). So a large k_eq (e.g., 1000000) means that the reaction is close to completion, and a very small k_eq (e.g., 0.00000001) means that the reaction barely occurs.

Chemical Equilibrium #2: Le Chatelier's Principle

Le Chatelier's Principle predicts what would happen to a system at equilibrium if certain conditions are changed. The general statement is:

If a chemical system at equilibrium experiences a change in concentration, temperature, pressure or volume, the equilibrium will be shifted to counteract this change, and a  new equilibrium will be established.

Now, let's break this statement down:

Change in Concentration

A + B ⇌ C + D

In the above reaction, if the concentration of C were increased, then the equilibrium must shift to counteract this change. In order to do so, the equilibrium will have to shift toward the reverse direction so that the excess C can be consumed.

If, instead, the concentration of C were decreased, then the opposite will happen. The reaction will have to shift toward the forward direction so that there can be more C.

Chemical Equilibrium #1: Introduction

What is equilibrium? 

Equilibrium is the state of a closed system at which two opposing reactions are simultaneously occurring at the same rate. In other words, in an equilibrium, the concentrations of all chemicals are constant.

(Note: even though the two reaction rates are equal to each other, it doesn't mean that the concentrations of the chemicals are equal)

Chemistry: How to Solve Titration Questions

Strong Acid + Strong Base Titration

1. Convert concentrations to number of moles
2. Subtract the smaller n from the larger n
3. Calculate -log (difference÷total volume)
4. If the larger n is of the acid, the result is the pH. Otherwise, it's the pOH.

Weak Acid+ Strong Base Tritation