buffers Flashcards
buffer solution
one that can resist changes in pH
they will return to a nominal pH value when small volumes of acid or base are added to them
always weak
how is a buffer solution prepared
weak acid + salt of a weak acid (made with a strong base)
weak base + salt of a weak base (made with a strong acid)
how does a buffer solution work
using an eqm system between weak electrolyte and salt of the weak electrolyte
ch3cooh + h20 – ch3coo- + h30+
what happens when acid and base is added to system
if acid is added
- h3o conc increase
- sysmte counteracts by increases backward rr
- decreases h3o conc and brings ph back down
if base is added
- h30 conc decreases
- system counteracts by increase forward rr
- increases h3o+ conc and brings the ph back up
nh3 + h20 – nh4+ +oh-
what happens when base or acid is added to system
is acid is added
- oh conc decreases/water is formed
- system counteracts by increasing forward rr
- the oh conc increases to original and brings ph back up
is base is added
- the oh conc increases
- system counteracts by increase backwards rr
- decreasing oh conc and bringing ph back down
buffer capacity
refers to how much acid or alkali can be added to a buffer solution before there is drastic change in pH value
more concentrated reagents used for buffer = higher buffer capacity
bicarbonate buffer system
homeostasis mechanisms that helps maintain the pH balance in the blood and other tissues
what happens when acid is added to bicarbonate buffer system
bicarbonate ion (hco3-) neutralises by forming carboante acid (h2co3)
what happens when base is added to bicarbonate buffer system
carbonic acid (h2co3) neutralises it by releasing hydrogen ion to form bicarbonate ion (hco3-)
use of bicarbonate buffer system
kidneys help regulate conc of bicarbonate ions by reabsorbing hco3- and secreting h+ into urine
phosphate buffer system
important mechanism for maintianing pH balance in the body, particulalry intracellular fluid and the kidney
differnet phosphates in buffer system
h2po4- (dihydrgeon phsphate) acts as a weak acid
hpo4(2-) (monohydrogen phosphate acting as a weak base
what happens when acid is introduced into phosphate buffer system
the hpo4 (2-) neutrliases it by forming h2po4-
what happens when base is introduced into phosphate buffer sysmte
h2po4- neutralises it by releasing hydrogen ion and forming hpo4 (2-)
use of phosphate buffer system
effective in kidneys - helps to buffer ph of urine
also buffers ph of cells, even tho conc in the blood is low compared to bicarbonate buffer system
biological system - buffer application
bicarbonate buffer system regulates blood pH ensuring our cells function optimally.
bicarbonate also moonlights as an ocean buffer keeping marine pH in check
buffer application in chemicla reactions
help stablise mixtures preventing whil pH swings
buffer application in analysitcal chem
they keep pH steady allowing for acurate results
buffer application in industrila process
buffers maintain optimal conditions in wastewater treament, pharmacueticals etc.
