pH Determination (EXPT 2) Flashcards
pH of 0 - <7
Acids
React with metals and bases.
Acids
Tend to taste sour.
Acids
Give off / contribute H+ ions into a solution.
Acids
aq stands for?
aqueous
A solution in which the solvent is water (dissolved in water).
aqueous (aq)
pH of > 7 - 14
Bases
Do not react with metals
Bases
React with acids
Bases
Tend to taste bitter
Bases
Give off / contribute hydroxide ions (OH-) to a solution.
Bases
pH of 7
Neutral
Neither acidic nor basic.
Neutral
Pure water is an example of?
Neutral
We can neutralize an acid with a base, or neutralize a base with an acid.
Neutralization
Ex. There are bases secreted in our intestines that neutralize the acid from our stomach.
Neutralization
A substance that changes color in the presence of an acid or base.
Indicator
Cabbage juice & litmus paper is an example of?
Indicator
Indicators change over a ____ space of pH, not sharply at one particular pH
narrow
Litmus paper pK
6.5
Methyl Orange pK
3.7
Phenolphthalein pK
9.3
Litmus turns ___ when adding hydrogen ions.
Red
Litmus turns _____ when adding hydroxide ion.
Blue
A chemical compound with the formula C20H14O4 (often written as “HIn” or “phph”.
Phenolphthalein
Often used in titrations, it turns colorless in acidic solution and pink in basic solution.
Phenolphthalein
An intensely colored compound used in dyeing and printing textiles.
Methyl Orange
- C.I. Acid Orage 52
- C.I. 13025
- helianthine B
- Orange III
- Gold orange
- Tropaeolin D.
Methyl Orange
Chemists use methyl orange as a indicator in the titration of ____ bases with ____ acids. It changes from red (pH 3.1) to orange-yellow (pH 4.4).
weak bases , strong acids
A measure of hydrogen ion concentration, [H+], in an aqueous (water) solution.
pH
Formulas of pH
pH = -log [H+]
pOH = -log [OH-]
pH + pOH = 14
The measures of the strengths of acids and bases, respectively.
pKa and pKb
The operator p may mean “take the ______ logarithm of”.
Negative
The smaller the value of pKa, the ______ the acid.
Stronger
The smaller the value of pKb , the _______ the base.
Stronger
Acid dissociation constant.
Ka
The greater the value of Ka , the ______ the acid.
Stronger
Base dissociation constant.
Kb
The greater the value of Kb , the ______ the base.
Stronger
______ bases grab protons more greedily.
Strong
Indication of Paracetamol.
Antipyretic, Analgesic
Direction to use of Paracetamol.
PO (by mouth)
Do not take this medication for fever for more than 3 days unless directed by your doctor. For adults, do not take this product for pain for more than 10 days (5 days in children) unless directed by your doctor.
Paracetamol
pH range of Paracetamol
5.5 - 6.5
Indication of Maalox
Antacid - used to treat the symptoms of too much stomach acid such as stomach upset, heartburn, and acid indigestion.
Direction for Use of Maalox
PO, after meals
If your acid problems persist or worsen after you have used this product for 1 week, seek immediate medical attention.
Maalox
pH range of Maalox
Approximately 8
Indication of Ceelin
Prevention and treatment of Vitamin
C deficiency in infants and children.
The most trusted and most prescribed Vitamin C supplement for kids which helps boost the immune system for their protection from sickness.
Direction for Use of Ceelin
PO, with or without food
pH range of Ceelin
1.0 to 2.5
Formula of Phenolphthalein.
C20H14O4
Phenolphthalein turns ____ in acidic solutions.
Colorless
Phenolphthalein turns ____ in basic solutions.
Pink
Title of Experiment 2?
pH Determination
