22478339
Description
Flashcards by Evian Chai, updated more than 1 year ago
|
Created by Evian Chai
about 4 years ago
|
|
| Question | Answer |
| What is the difference between strong/weak acids and bases? | Strong acids disassociate completely and are proton donors Weak acids do not dissociate completely and are proton donors Strong bases accept protons more readily than weak bases |
| What is the meaning of the term pH? | It is a measure of free hydrogen ion concentration |
| What is the pH of the following: Blood Living range of blood Water | 1. 7.35-7.45 2. 7.0-8.0 3. 7 [H+]=[OH-]=10^-7M each |
| What is a buffer made of? How does it work? When does a buffer work best? | Buffers are made of a weak acid and its conjugate base At the pKa |
| The equivalence point on a titration graph looks like.... and represents .... The midpoint on a titration graph looks like.... and represents .... | A sharp vertical increase, The point where titrant completely neutralises the analyte The middle of the section between the two equivalence points. Represents the point where half the acid is disassociated, and is equal to the amount of conjugate base (aka the pKa) |
| What is the Henderson Hasselback equation? | pH=pka+log([CB]/[WA]) |
| What is the bicarbonate buffer system and its importance? What is its pKa? | H2CO3-->HCO3- pKa=6.1 |
| What is the phosphate buffer system and its importance? | H2PO4- --> HPO4^2- pKa=6.8 |
| What is the protein and NH4+ buffer system and its importance? | Protein-->Protein - Protein+ --> Protein |
| What is the critical pH and how can it vary oral cavity? | Highest pH where there is a net loss of mineral from teeth About 5.5 Depends on the amount of Ca2+ in saliva because it forms calcium phosphate (increasing reduces critical pH, meaning teeth can withstand lower pH) |
| What is the equation for pH? | pH=-log[H+] |
| What is the pKa? Where is the pKa on a titration graph? What does a lower pKa mean in terms of acid strength? | When acid is half disassociated and [WA]=[CB] The midpoint Lower means stronger |
| If pKa>pH, amino acid is protonated/unprotonated If pKa<pH, amino acid is protonated/unprotonated | 1. Protonated (amino acid stronger, wins) 2. Unprotonated (solution stronger, wins) |
| Does the zwitterion buffer? | No |
| What AA is a good psychological buffer? | Histidine, because its pKa is around 7.4 Many histidine groups on hemoglobin, so its a good buffer |
| What is the pKa of oxyhemoglobin and deoxyhemoglobin? | Oxy: 6.8 Deoxy: 7.8 |
Want to create your own Flashcards for free with GoConqr? Learn more.