Posted by Kate on Friday, November 21, 2008 at 8:55am.
You have not said what grade you are.
I'll answer the first part last.
pH scale is simple numerical means of assessing how acidic a solution might be. The concentration of acid (more correctly the hydrogen ion concentration) can cover a range from 0.1 mole per litre down to 0.00000000000001 moles per litre, which a huge range and very difficult to visualise. Thus there is a scale from 1 to 14 which covers this range, the pH scale. It turns out that neutral is pH 7, acid solutions have number less than 7 and alkaline numbers greater than 7.
Many reactions, especially biological reactions involving enzymes, are very sensitive to the acidity of the solution, i.e. the pH. Slight changes in the pH can make the reaction go faster or slower or not at all. Indeed low or high pH values can kill cells and denature (=unravel) enzymes. Thus it is important to control the pH of a reaction or the medium in which you have a biological study.
Does this help?
Related Questions
Biology - Whats the history/background on the pH Scale
university chemistry - this is for a chemistry laboratory experiment called &...
science HElp - Ph scale Which on is true A substance with ph is twice as acidic...
science - Can you tell me on the pH scale what no.s are acid and what are alkali...
biology -urgent...highly confused - How does pH affect the activity of catalase...
Chem Webwork - Complete the table below: What are the pH values if you take into...
chemistry - "experiment: spectrophotometric determination of the acid ...
Chemistry - Classify each of the following solutions as acidic, basic, or ...
Chemistry - Which solution below has the highest concentration of hydronium ions...
Science - Which solution below has the highest concentration of hydronium ions? ...
For Further Reading
