Chem Lab final

molecules dissolve in water becasue they have the ability to hydrogem bond (they have F,O,N,Cl in their structure).  The more sites of hydrogen bonds the more soluble the molecule is.

• like dissolves like (take the whole molecule)
• methanol is soluble in water
• octanol is not

salicylic acid + acetic anhydride = aspirin + acetic acid

phenol group on salycilic acid transformed into an ester group in aspirin

• carboxylic acid
• ester
• benzene ring

the strong acid (phosphoric acid)

• yes old aspirin often has a vinegar smell due to the precence of acetic acid
• test by adding iron (III) chloride to aspirn it will turn violet if salicylic acid is present.

• 1:1 ratio of moles of salicylic acid used and aspirin produced
• every 1 mole of salicylic acid used will equal 1 mole of aspirin.
• 1) determine what 1 mole of salicylic acid is (C₇H₆O₃) 1mole = 138g found from periodic table
• 2) use how many grams of salicylic acid you started with 3.0grams and convert that to moles 3.0g(1mol/138g)=0.02 mol salicylic acid
• 3) determine grams per mole of aspirin (C₉H₈O₄) = 180g/mol
• 4) convert salicylic acid mole to grams of aspirin 0,02mol salicylic acid(180g/1mol)=3.6g aspirin

(mass of dried product made g /theoretical yield g )x100= percent yield

• Acid is proton donor and produce hydronium ions (H₃O⁺)
• Bases are proton acceptor and produce hydroxide ions (OH^-)

The amount of hydronium ions in a solution (H₃O⁺)

basic

• [H₃O⁺][OH^-]=1.0X10^-14
• as long as you have either the pH or the amount of OH or H3O then you can figure out all of the other numbers
• (remember 1X10^-14 is a ver small number compared to 10^-1)

buffer = a solution that keep the pH constant consists of a weak acid and conjugate base or weak base and conjugate acid

• the acid shock absorbs the hydroxide ions when added to system and the base shock absorbs the hydronium ions when added to the system
• (acid absorbs base)(base absorbs acid)

It decreases it making it more acidic

• 1calcium carbonate neutralizes 2HCl
• 1magnesium hydroxide neutralizes 2HCl
• 1 sodium bicarbonate neutralizes 1HCl
• 1aluminum hydroxide neutralizes 3HCl

• 1.) start with acid + antacid
• 2.) add acid until all of the antacid is consumed (color change to yellow)
• 3.) add base until color change to blue
• 4.) Base and aicd on 1:1 ration (amount base added = amount acid used to consume antacid tablet)
• 5.) ml used to consume antacid = acid added (total) - base added

moles/L

moles= molarity x Liters

• know the ratio of consumption 1:2, 1:1, 1:3 etc.
• determine moles of active ingredient in tablet (grams to moles conversion)
• convert moles of tablet to moles of HCl based upon ratio

the point at which a molecules surface carries no net electrical charge

at its isoelectic point the protein will precipitate out of solution

at a pH above or below its isoelectic point

overall charge is positive becasue there are excess H⁺ in solution

overall charge is negative becsasue there are excess OH^-in solution

The most abudant protein in milk