In chemistry, pH (, denoting 'potential of hydrogen' or 'power of hydrogen') is a scale used to specify the acidity or basicity of an aqueous solution. Acidic solutions (solutions with higher concentrations of H+ ions) are measured to have lower pH values than basic or alkaline solutions.
The pH scale is logarithmic and inversely indicates the concentration of hydrogen ions in the solution. This is because the formula used to calculate pH approximates the negative of the base 10 logarithm of the molar concentration of hydrogen ions in the solution. More precisely, pH is the negative of the base 10 logarithm of the activity of the H+ ion.At 25 °C, solutions with a pH less than 7 are acidic, and solutions with a pH greater than 7 are basic. Solutions with a pH of 7 at this temperature are neutral (e.g. pure water). The neutral value of the pH depends on the temperature – being lower than 7 if the temperature increases. The pH value can be less than 0 for very strong acids, or greater than 14 for very strong bases.The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. Primary pH standard values are determined using a concentration cell with transference, by measuring the potential difference between a hydrogen electrode and a standard electrode such as the silver chloride electrode. The pH of aqueous solutions can be measured with a glass electrode and a pH meter, or a color-changing indicator. Measurements of pH are important in chemistry, agronomy, medicine, water treatment, and many other applications.
1.00 g of formic acid and 1.00 g of potassium formate acid are dissolved in enough water to give 100.0 ml of solution. Calculate the pH of the solution.
>> I'm not really sure how to start this. These are two acids being mixed together... Would there be a reaction? I'm very confused on how...
I'm posting this here because I don't know the legitimacy of the topic and whether it qualifies for discussion in the other physics sections.
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Does anyone know whether there is any university having researches on General Relativity itself, not its application in Astrophysics? If so, what mathematics do I need rather than differential geometry?
50.00 mL of 0.1000 M citric acid (Ka = 7.41 x 10^-4).
titrated 50.00 mL NaOH added.
Calculate pH.
I have equal moles of Acid and equal moles of Base. But, I am titrating a strong base into a weak acid. So, instead of my pH being 7, I assume it should be just above 7. But, I am not...
1. what is the pH of a solution that contains 1.56X 10^5 M hydrogen ions ?
2. Is there a pH above which the molarity of hydrogen of water is higher that the molarity of hydrogen ions derived from the dissolved chemical, and what is it?
3. What is the pH of 10^-8 M solution of HCl, when HCl...
Is it really possible to have strong acid/bases with a negative pH in practice, or is it purely theoretical. Like we say 10M HCl has pH = -1, does it really?
Is there something that limits the range of possible pH values for a solution?
Hi ppl, I got a problem with this question
Calculate the pH of 2.00dm3 of an aqueous solution which contains 12.4g of CH3NH2 and 13.5g of methylammonium chloride, CH3NH3+Cl-. The Pka of methylammonium chloride is given as 10.8
Thanks a lot for any help,
Joe
Changes Of pH values...
Could You Guys Help Me Out With THis Question Please,
Why would the pH of a solution not change by much when a little amount of acid or alkali are added to the solution??
I know this is simple, but I am a bit confused
1) find the pH of 12.1 M HCl - the negative log gives me -1.8. What am I doing wrong
2) 50% NaOH (roughly 15 M) - I am not sure how to do this one either
thanks
nautica
Hi I just need to know if there was a standard concentration for the acid and base that I am going to use to change the pH of the media that I am making for bacteria? I am using NaOH and H2SO4. THanks
Anybody got a relationship between fresh water PH level, and amount of + or - net charge, say per cubic meter of H20, at a nominal temperature. Rivers are usually alkaline, thefore have a net -charge, the cubic meters flowing at X meters/sec, and therefor function effectively as a fat wire. I...
So I have an chem assignment which I've been going through for the past week or so, but the last question has provided somewhat of a stumbling block. Here it is,
So from the question, I have gathered the following,
High pH solutions absorb at higher wavelenghts. Whereas low pH solutions...
I know that Kw is equilibrium constant for water..
but what is Ka and Kb? I Is Ka equilibrium constant for acid and Kb equilibrium constant for Kb? If so how can u find those??
For example..here is an equation
Kw = [OH-][H+] = 1e-14
What is the Ka and the Kb?
Someone told me that...
__________HA <------> H+ + A-
initial (mol) .1 ________ 0 ___ 0
change __ -x _______ +x ___ +x
final _____.1-x _______ x ___ x
Ka = 10^-8
find pH of .1 mol acid
since ka X 100 = 10^-6 < .1 can use initial concentration: .1-x = .1
Ka = [H+][A-]/[HA]...
Often while channel surfing late at night, I'll see an infomercial with some doctor who claims that all ailments are caused by too much acidity in the body. So far, I have always flipped the channel immediately and given it no further thought. Now while web-surfing I found this website which...
here is a buffer problem in my HW that I'm not sure how to do.
Plz help me. Plz show me how. Thanks a lot.
Formula: pH = pKa + log([B-]/[HB])
***A buffer is made up of 0.500 L each of .300 M KH2PO4 and .400 M K2HPO4. Calculate
a) The pH of the buffer after the addition of 0.0500 mole of...