pH research :)

Heyy everyone!!! :)

Ok, well since the experiment has been completed and pictures have been posted, i thought it would be a good idea to be doing some more background research for my research experiment. Not only is it needed for the introduction of my report, but it would also help to answer some of my questions that i have concerned with the experiment.

Ok well today ive decided to some research on pH, because as you know ive been testing the pH levels of my four different liquids- plain, tap water, chlorinated, pool water, chlorinated pool water with liquid pool cover and chlorinated pool water with solid pool blanket, which is actually just the same as normal chlorinated, pool water- so i guess that makes it three different liquids! Haha. So anyway here is my research: (note: i have paraphrased)

What exactly is Ph?
pH is a measure of the hydrogen ion concentration. That pH scale we talked about is actually a measure of the number of H+ ions in a solution. If there are a lot of H+ ions, the pH is very low. If there are a lot of OH- ions, that means the number of H+ ions is very low, so the pH is high. It is also a measure of the acidity or alkalinity of a solution, numerically equal to 7 for neutral solutions, increasing with increasing alkalinity and decreasing with increasing acidity. The pH scale commonly in use ranges from 0 to 14.

Who uses the scale and a bit more on what it’s used for?
Scientists use something called the pH scale to measure how acidic or basic a liquid is. Although there may be many types of ions in a solution, pH focuses on concentrations of hydrogen ions (H+) and hydroxide ions (OH-). The scale goes from values very close to 0 through 14. Distilled water is 7 (right in the middle). Acids are found between a number very close to 0 and 7. Bases are from 7 to 14. Most of the liquids you find every day have a pH near 7. They are either a little below or a little above that mark. When you start looking at the pH of chemicals, the numbers go to the extremes. If you ever go into a chemistry lab, you could find solutions with a pH of 1 and others with a pH of 14. There are also very stong acids with pH values below one such as battery acid. Bases with pH values near 14 include drain cleaner and sodium hydroxide (NaOH). Those chemicals are very dangerous.

Definitions (i know all are not useful for this experiment, but they are interesting and helped me to understand the whole acid base thing better)
Acid: A solution that has an excess of H+ ions. It comes from the Latin word acidus that means "sharp" or "sour".
Base: A solution that has an excess of OH- ions. Another word for base is alkali.
Aqueous: A solution that is mainly water. Think about the word aquarium. AQUA means water. Strong Acid: An acid that has a very low pH (0-4).Strong Base: A base that has a very high pH (10-14).
Weak Acid: An acid that only partially ionizes in an aqueous solution. That means not every molecule breaks apart. They usually have a pH close to 7 (3-6).
Weak Base: A base that only partially ionizes in an aqueous solution. That means not every molecule breaks apart. They usually have a pH close to 7 (8-10).
Neutral: A solution that has a pH of 7. It is neither acidic nor basic.

The scale:
The scale is logarithmic so a change of one pH unit means a tenfold change in acid or alkaline concentration. A change from 7 to 6 represents 10 times the concentration, 7 to 5, 100 times, and so on.

Factors that affect pH levels? (this is something that i was really interested in finding out)
Air pollution, primarily from automobile exhaust and fossil fuel burning increase concentrations of sulfur and nitrogen oxides in the air. Therefore when it rains these particles or components turn it to "acid rain" and increase the acidity of lakes and streams.
Runoff that contains wastewater from farms, logging or mining sites, and other commercial and residential developments sends chemicals and other constituents that alter pH levels.

Ph indicators:
A pH indicator is a chemical compound that is added in small amounts to a solution so that the pH (acidity or alkalinity) of the solution can be determined easily. Hence a pH indicator is a chemical detector for protons (H+). Normally, the indicator causes the colour of the solution to change depending on the pH.

Ok now this is the question that i am also really interested in, and will definitely be very useful for my report. “Do different Ph levels affect the rate of evaporation in different liquids?”
The evaporation of liquids depend upon things such as air flow, relative, humidity, wind, temperature, surface area etc. Therefore different chemical characteristics such as pH or alkalinity do not have an effect on the evaporation process.

References
http://encyclopedia.kids.net.au/page/ph/PH
http://www.chem4kids.com/files/react_acidbase.html
http://www.bpa.gov/corporate/kr/ed/kidsinthecreek/topics/waterquality/ph.htm
http://encyclopedia.kids.net.au/page/ph/PH_indicator

xoxo Mira