A hydrogencarbonate indicator (hydrogencarbonate indicator) is a type of pH indicator that is sensitive enough to show a color change as the concentration of carbon dioxide gas in an aqueous solution increases. The indicator is used in photosynthesis and respiration experiments to find out whether carbon dioxide is being liberated.[1] It is also used to test the carbon dioxide content during gaseous exchange of organisms. When the carbon dioxide content is higher than 0.04%, the initial red colour changes to yellow as the pH becomes more acidic. If the carbon dioxide content is lower than 0.04%, it changes from red to magenta and, in relatively very low carbon dioxide concentrations, to purple.[1] Carbon dioxide, even in the concentrations found in exhaled air, will dissolve in the indicator to form carbonic acid, a weak acid, which will lower the pH and give the characteristic colour change.[1] A colour change to purple during photosynthesis shows a reduction in the percentage of carbon dioxide and is sometimes inferred as production of oxygen, but there is not actually any direct evidence for it.[2]
Great care must be taken to avoid acidic or alkaline contamination of the apparatus in such experiments, since the test is not directly specific to gases like carbon dioxide.[2]
^ abcBBC Bitesize - GCSE Biology - Gas exchange in plants
^ abChatterjee, Sananda. A Chemical Analyser's Guide, p.111
and 25 Related for: Bicarbonate indicator information
A hydrogencarbonate indicator (hydrogencarbonate indicator) is a type of pH indicator that is sensitive enough to show a color change as the concentration...
manufacture. In diagnostic medicine, the blood value of bicarbonate is one of several indicators of the state of acid–base physiology in the body. It is...
the pupil breathes out. A suitable carbon dioxide indicator, such as limewater or bicarbonateindicator shows the increased presence of carbon dioxide in...
reverse this acidotic condition. As metabolic bicarbonate production becomes exhausted, and extraneous bicarbonate infusion can no longer reverse the extreme...
When carbon dioxide dissolves in water, it forms carbonate and mainly bicarbonate (HCO−3), which causes ocean acidification as atmospheric CO2 levels increase...
absorbs carbon dioxide from the air, which is then slowly converted into bicarbonate and hydrogen ions (essentially creating carbonic acid). CO 2+ H 2O ⇌...
gypsum, which are largely made up of calcium and magnesium carbonates, bicarbonates and sulfates. Drinking hard water may have moderate health benefits....
values, it also measures blood pH, and the level and base excess of bicarbonate. The source of the blood is reflected in the name of each test; arterial...
intense anaerobic exercise is among others due to factors including the bicarbonate buffer system. The body tries to compensate for the accumulation of lactate...
the other hand, alkalinity is completely dominated by carbonate and bicarbonate plus a small contribution from borate. Although alkalinity is primarily...
achieved by 2030. Progress towards each target is being measured with one indicator each. The first seven targets are outcome targets: Reduce marine pollution;...
information.[citation needed] An ABG test can also measure the level of bicarbonate in the blood. Many blood-gas analyzers will also report concentrations...
broken down to pyruvate and carbon dioxide (CO2). Production of sodium bicarbonate (NaHCO3) as well as ammonia (NH3) from the use of sodium citrate and...
fluid (for example, glucose, amino acids, uric acid, phosphate, and bicarbonate). Fanconi syndrome affects the proximal tubules, namely, the proximal...
over one-and-a-half times the upper limit of the reference range. Serum bicarbonate less than 24. Karnofsky performance status less than 60. Extensive stage...
as an acid or a base. Water, amino acids, hydrogencarbonate ion (or bicarbonate ion) HCO−3, dihydrogen phosphate ion H2PO−4, and hydrogensulfate ion...
products can be generated from symmetrical alkenes: Using TsOH; sodium bicarbonate (NaHCO3); dimethyl sulfide (DMS) gives an aldehyde and a dimethyl acetal...
300 mg bolus. The second dose is given as a 600 mg bolus. Bicarbonate, given as sodium bicarbonate, works to stabilize acidosis and hyperkalemia, both of...
the weak unstable carbonic acid (H2CO3) can lose one proton to form bicarbonate anion (HCO− 3) and lose a second to form carbonate anion (CO2− 3). Both...
calcium carbonate to dissolve as bicarbonate. Where rainfall is adequate but not excessive, the calcium bicarbonate is carried down into the B horizon...
dissolved bicarbonates (as occurs when irrigating with high-bicarbonate waters). The accumulation of alkalinity in a soil (as carbonates and bicarbonates of...
chemical reaction produces carbonic acid (H2CO3) which dissociates into a bicarbonate ion (HCO−3) and a hydrogen ion (H+). The presence of free hydrogen ions...