0
no
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
What is the case hardness of EN-19?
The hardness depends on the thermal and chemical treatment and is between 200 HB and 375 HB.
What does hb stand for in football?
Halfback
Why is hemoglobin said to combine reversibly with oxygen?
As I understand it, and very simplistically, I think it means that the bonding is easily reversible. In other words, the O2 is readily bound to haemoglobin but is also readily released depending on the partial saturation levels of Oxygen (PO2) that are encountered by the RBC. * In the pulmonary capillaries the PO2 is high and therefore the amount of O2 bound to Hb is also high (fully saturated). In the systemic capillaries the PO2 is low and hence the O2 dissociates with the Hb and diffuses into the tissue cells. (The Hb is then said to be partially saturated). Although PO2 is the major factor in the binding of O2 to Hb, other factors also effect this process. * Acidity: Lactic acid and carbonic acid generated during exercise lowers the pH of the blood which promotes the release of O2 from Hb. Hence the exercising tissues which require extra O2 help create a situation where more O2 is available. * PCO2 effects the transport and delivery of O2. Increased metabolic activity of the tissue cells produces more CO2 as waste, which promotes release of O2 from Hb through an associated decrease in pH (see above point) and also as part of an O2/CO2 cycle. It goes something like this: In the pulmonary capillaries, O2 diffuses from the alveolus into the RBC. It binds to Hb to create oxyhaemoglobin and H+ ions. Bicarbonate ions combine with the H+ ions to create carbonic acid which, under the influence of the enzyme carbonic anhydrase, dissociates into CO2 and water. The CO2 diffuses into the alveoli and is expelled by the lungs. The RBC then travels in the blood to the systemic capillaries and CO2 diffuses from the tissues (as a waste product of tissue cell metabolism) into the RBC. A small percentage of the CO2 binds to the globin in Hb, forming carbaminohaemoglobin, this causes O2 to dissociate from the haem part of the Hb. The O2 then diffuses from the RBC into the tissue cells. Most of the CO2, under the influence of the enzyme carbonic anhydrase, combines with H2O to become Carbonic acid which then dissociates into Bicarbonate ions (HCO3-) and H+ ions. The H+ ions promote the dissociation of O2 from the haemoglobin by taking the place of the O2 in the Hb molecule. * Increased temperature also has a minor effect of promoting the release of O2 from the Hb. Anatomy and physiology books such as "Anatomy and Physiology - From Science to Life" by Jenkins Kemnitz and Tortora is a fabulous resource for understanding the intricacies of this process.
What is Hb H?
A : Hb H is Hemoglobin H, which is a type of hemoglobin which is normally found in adult human beings. Hemoglobin is the oxygen-carrying chemical compound in our red blood cell.
Why do the red blood cells carry less oxygen in a smoker?
Red blood cells contain a protein known as haemoglobin (Hb) which is responsible for carrying about 98% of the body's oxygen (the rest is dissolved in the blood). However oxygen is not the only thing that binds to Hb. Both carbon dioxide (CO2) and carbon monoxide (CO) can also bind to it as well (both of which are chemicals produced in cigarette smoke). The binding of CO2 to Hb is normal, and is how the majority of CO2 in the body is trasported to the lungs for exhalation (as it is a bi-product of energy production in the body). However, both CO2 and CO have higher affinities for Hb (i.e. they are more likely to bind to Hb) in the blood, and so when there is more CO and CO2 around, such as when smokers inhale cigarette smoke, the Hb is more likely to bind CO and CO2 than oxygen. CO2 is far more common than CO, and Hb's affinity for it is lower as well. Hb has an incredibly high affinity for CO which explains why it is so toxic to humans as the Hb it binds to is more or less left unusable in the body. This is my understanding of this all at a 2nd year university level of physiology, but I believe it more or less explains everything.
What is the base-dissociation constant for a weak base?
Suppose: B- is symbol for any (soluble) base.Equilibrium of a base when diluted in water:B- + H2O HB + OH-Equilibrium constant:Keq = [HB] * [OH-] / [B-] * [H2O]The base dissociation contant is defined by:KB = [HB]*[OH-]/[B-]So, KB = Keq*[H2O] = Keq*55.6 mol/L
At the equivalence point if pH of HA is 8 and the pH of HB is 9 which is the stronger acid Also which conjugate base would be stronger A or B?
Conjugate base B- is stronger, it has a higher pH at Eq.P.Your first (and also the original) question is answered as follows:At first one has to suppose that the concentrations of HA and HB are the same! 1)Eq.P. at pH=8: You need less OH- (titrant) to reach this, so the acid donated its last proton easier, so it was stronger. (Eq.P. at pH=7 means it isn't weak at all)1) It is more accurate to compare pH value's half-the-wayof titration, because pH1/2way is exactly equal to pKa value of the acid concerned AND it is independent of concentration: it is buffered!!!
Is buffer capacity the same if determined by titration with a strong base instead of a strong acid?
It depends a bit on the buffer itself, but it is usually true. Generally speaking, a buffer is a solution composed of a weak acid (or base) along with its conjugate base (or acid). Usually, the two components (let's call the HA and A- for a weak acid and its conjugate base) are added in equal concentrations. If this is the case, then it is also true that the pH of the solution is equal to the pKa of the weak acid, a very useful fact. If the concentration of two HA and A- are equal, then the buffer capacity should be the same using a strong acid or strong base. However, you can also make a buffer with unequal concentrations of HA and A-. This is still considered a buffer solution, and it will resist change to pH in both directions, but unequally now. If you have a higher concentration of HA than A-, then the buffer will have a higher capacity to resist pH change if you add a strong base (because the base will be deprotonating HA, which you have more of). If you added a strong acid instead, then you would protonate all the A- faster (than you would deprotonate HA with the same amount of strong base), and so it would have a lower buffer capacity. This discussion works equally well if you are using a weak base (B) and its conjugate acid (HB+) instead, except everything is switched!
Why hcl is used in Hb estimation?
Hb forms acid-hematin by reacting with Hcl.
Is distill water a acid or a base?
In general it is said to be neutral, but having said so you can (and Mr. Lewis did in his theory on acid and base) see water as both an acid and as base:Acid behaviour of H2O, donating a proton to base B- H2O + B- --> OH- + HB (1)base behaviour of H2O, accepting a proton from acid HB H2O + HB --> H3O+ + B- (2)Ampholyte*) behaviour: donating a proton to itself as acceptor(H2O)donor + (H2O)acceptor OH- + H3O+which makes water having both concentrations [H3O+] = [OH-] = 1.0*10-7, so: pH = 7*) Ampholyt means: both donor and acceptor, at the same time, 'like twins'
Prove that Kw equals product of Ka and Kb for an acid-base pair in water?
dissociation of acid in water: A + H2O <-> A- + H3O+ with dissociation constant Ka = [A-][H3O+]/[A][H2O] = [A-][H3O+]/[A]. dissociation of base in water: B + H2O <-> HB+ + OH- with dissociation constant Kb = [HB+][OH-]/[B][H2O] = [HB+][OH-]/[B] dissociation of water in itself: 2H2O <-> H3O+ + OH- with dissociation constant Kw = [H3O+][OH-]/[H2O]^2 = [H3O+][OH-] where [H2O] has been ommitted because it is a pure liquid. substituting relations for Ka and Kb into Kw gives: Kw = [H3O+][OH-] = (Ka[A]/[A-])(Kb[B]/[HB+]) = KaKb where [A] = [HB+] and [B] = [A-].
Why Hydrochloric acid is used for hemoglobin estimation?
to convert the Hb to acid-hematin which is a brown coloured complex.
What factors determine pH of buffering?
If a strong acid is mixed with a weak base, pH=pKa+/-1 in the buffer region.Corrected:If a strong base is mixed with a weak acid pOH= pKb +/-1 ( pH=(14 - pKb)+/-1) in the buffer region[Remember: For one conjugated pair of weak acid (a = HB) AND its weak base (b = B-):pKa + pKb = 14.0andpH + pOH = 14.0
Is distilled water a acid or a base?
In general it is said to be neutral, but having said so you can (and Mr. Lewis did in his theory on acid and base) see water as both an acid and as base:Acid behaviour of H2O, donating a proton to base B- H2O + B- --> OH- + HB (1)base behaviour of H2O, accepting a proton from acid HB H2O + HB --> H3O+ + B- (2)Ampholyte*) behaviour: donating a proton to itself as acceptor(H2O)donor + (H2O)acceptor OH- + H3O+which makes water having both concentrations [H3O+] = [OH-] = 1.0*10-7, so: pH = 7*) Ampholyt means: both donor and acceptor, at the same time, 'like twins'
What is the medical abbreviation for HB or hb?
HB
What is the unit of hb?
hb volume unit
What is a hb pencil?
An HB pencil is just a No. 2 Pencil HB stands for Hard Black
