Showing posts with label Acids/Bases. Show all posts
Showing posts with label Acids/Bases. Show all posts

Wednesday, March 9, 2016

Acid Bases Quiz Reflection

Today I took my Acids/Bases 18 question quiz, and needless to say, I most likely failed. I guessed on probably 5 of the questions, and even the ones that I did answer, I was unsure of. I really need to devote much more time to studying, or I am going to fail chemistry. It is crucial to reinforce my skills outside of the classroom and I haven't really been doing that at all lately. I should have been looking at resources like these:

http://www.chem4kids.com/files/react_acidbase.html
http://www.chemtutor.com/acid.htm

This is particularly informational^

https://www.khanacademy.org/science/chemistry/acids-and-bases-topic

% Acetic Acid In Vinegar Lab



Today we conducted a lab to calculate the % Acetic Acid in vinegar. It is extremely similar to the unknown molar mass lab to carry out. We made a standard KHP solution, titrated it, and repeated the process with a vinegar solution. Using some stoichiometry and a calculator, you can carry out the necessary calculations to figure out the % Acetic acid.
Here is what a titration should look like (the middle).

Strong Acids

Strong Acids meet a few criteria, and protonate more in water than weak acids.

You can identify a strong acid by checking the PH, It should be relatively low. Also when written out in a BCE, the acid will have a formula in which Hyrdrogen atoms outnumber Oxygen atoms by at least two or more.

Unknown Acid Lab

Today we began a lab in which the task is to calculate the molar mass of an unknown acid. This was accomplished by making a standard of KHP solution, then dissolving some of the unknown acid in water. We titrated the solution using NaOH as a base and Phenolphthalein as an indicator. Once done with that, we did some calculations and found out to our surprise that it was the aspirin we had made 1st semester!


Here is a video for help with understanding titrations. 

Tuesday, March 8, 2016

The PH Scale


The PH scale is used to measure acidity and basic-ness. 7 has a neutral stance, whereas anything below 7 is considered acidic and above is basic. the scale runs to 14, and is a measure of the H+ concentration of Ions in a solution. The PH of a solution can be determined using some stoichiometry and logarithms. Below is a section of the PH scale with references.

Acids and Bases Introduction

Ah, so you want to learn about acids and bases. Good news... I can't help you, unfortunately, because I just started learning about them myself. However, I do have a BASIC understanding... haha.

Anyways, the acidity of an acid BASICally refers to the concentration of H+ ions contained in the solutions. The higher the H+ concentration, the more acidic it is, and the more terrifying. 

The same goes for bases but with OH- Ions instead. 

When a strong acid is dissolved in water, it heats up. 

In some cases, Acids produce H+ ions, but in other cases when reacted with certain bases, they form conjugate pairs