scholarly journals KAJIAN EKSTRAK ETANOL BUNGA BOGENVIL (Bougenvillea spectabillis Willd) SEBAGAI BIOINDIKATOR ASAM BASA

KOVALEN ◽  
2017 ◽  
Vol 3 (3) ◽  
pp. 277
Author(s):  
Nurhaeni Nurhaeni ◽  
Fitri A Bande ◽  
Rismawaty Sikanna

Studies of ethanol extract of bougainvillea flowers (Bougenvillea spectabillis Willd) as bioindicators of the acid-base has been done. The aims to determine the content of chemical compounds contained in extracts of bougainvillea flowers and bougainvillea flower extract pH stretch. Achievement of the objectives has done through the test of ethanol extract of bougainvillea identification of compounds and the determination of the acid-base stretch of pH indicator is. The obtained results showed that bogenvil ethanol extract containing flavonoids with 401 nm absorption and provided a color change in the acid and alkaline condition the color is yellow. The appropriate acid-base titration is used as bioindicators of a strong acid titration with a strong base, weak acid with a strong base and a weak base with a strong acid.Keywords: Flowers bougainvillea, indicators, bases acid titration

INDIAN DRUGS ◽  
2019 ◽  
Vol 56 (03) ◽  
pp. 77-79
Author(s):  
G Vambhurkar ◽  
A. Jagtap ◽  
A. Gavade ◽  
M Kengar ◽  
M Bhutkar ◽  
...  

In acid-base titration or acid-base neutralization reaction the change in color due to change pH of the solution is caused due to a third substance which is termed as acid-base indicator or pH indicator. Every indicator shows different range of colors at different pH ranges. Synthetic indicators have been widely employed as indicators in acid-base titrations; however, due to environmental pollution, availability and cost, natural compounds are best alternates. Natural pigments in plants are highly colored substances and may show sharp color changes with variation in pH. In the present study an attempt has been made to extract natural indicator from flower of Aristolochia bracteolate. The equivalence points of the titrations namely strong acid-strong base, strong acid-weak base, weak acid-strong base and weak acid weak base titrations, using flower extract of A. bracteolate were coincident with the equivalence points obtained by the synthetic indicator phenolpthalein. From the results of the study, it may be concluded that ethanolic extract of A. bracteolate flower as an indicator for acid-base titration could be effectively employed as a substitute to the synthetic acid-base indicators.


2019 ◽  
Vol 7 (9) ◽  
pp. 118-122
Author(s):  
R. F. Pagariya

Indicators used in acid-base titration show well marked changes of colour in certain intervals of pH. Most of these indicators are organic dyes and are of synthetic origin. Today synthetic indicators are the choice of neutralization titrations. But due to environmental pollution, availability and cost, the search for natural compounds as an acid-base indicator was started. The present work highlights the use of the ethanolic extract of the corolla of Roselle (Hibiscus sabdariffa) as a pH indicator in strong acid-strong base, strong acid weak base, weak acid strong base and weak acid-weak base titrations. This natural indicator is easy to extract as well as easily available. The results showed that the Roselle’s corolla indicator gave red color in acidic solution, while green in basic solution. The comparison indicators used in this research were phenolphthalein, methyl red and phenol red. Hopeful results were obtained when it was compared against standard synthetic indicators. The equivalence points obtained match with the equivalence points obtained by standard indicators. Therefore this natural indicator is found to be useful, economical, simple, precise and eco-friendly for acid base titration.


2012 ◽  
Vol 1 (12) ◽  
pp. 420-422 ◽  
Author(s):  
Sajin Kattuvilakam Abbas

Indicators help to determine the equivalence point in acid – base titrations (neutralization titrations). They show sharp color change with respect to change in pH. Commonly used indicators for neutralization titrations are synthetic in nature. They are found to posses hazardous effects in human body. The highly colored pigments obtained from plants are found to exhibit color changes with variation of pH. A study has been done to investigate the indicator activity of aqueous extract of flower pigments and compared with that of already existing synthetic indicators. Pigments were extracted using hot water and a definite volume was added which gave accurate and reliable results for all the four different types of neutralization titrations - strong acid against strong base, strong acid against a weak base, weak acid against strong base and weak acid against weak base. The work proved to be acceptable in introducing flower pigments as a substitute to the synthetic acid-base indicators.DOI: http://dx.doi.org/10.3329/icpj.v1i12.12452 International Current Pharmaceutical Journal 2012, 1(12): 420-422


2020 ◽  
Vol 9 (4) ◽  
pp. 191-198
Author(s):  
Andi M. Rendi ◽  
Supriadi Supriadi ◽  
Suherman Suherman

Cage plants (Canavalia virosa) are classified as nuts. This study aims to prove the flowers of the cage plants as acid-base indicators and determine the type of acid-base titration that is suitable for indicators of cage plants. The flowers of the cage plants were macerated with ethanol. Extras were tested as indicators in acid-base solutions, buffer solutions, and compared with phenolphthalein and methyl orange for acid-base titration, namely: strong acid with a strong base, a weak acid with a strong base, and weak base with strong acid. The results obtained in this study, namely: flower extracts of cage plants in strong red acid, in weak acid pink, in strong green bases, and weak bases in light green. In a buffer solution of pH 1 to pH 11, the flower extract of the cage plants gives 4 color groups, namely: a buffer solution with pH 1 colored red, pH 3 colored pink, pH 5 to pH 9 being light green, and pH 11 being dark blue. Cage plant flower extract can be used as an indicator of acid-base, cage plant flower extract can be used on strong-base strong acid titration, strong weak-acid base, and weak-strong base acid titration.


2017 ◽  
Vol 5 (1) ◽  
pp. 29
Author(s):  
Rahmawati Rahmawati ◽  
Siti Nuryanti ◽  
Ratman Ratman

Dadap red (erythrina crista-galli L.) is belonged to the legumes (fabaceaea) family which, is one of the flowering shade plants that often used as an ornamental plant. This plant has a bright red flower, a taproot with root nodule bacteria nitrogen fixation and compound leaf consists three strands on each stem. This research is climed to proves that the extract of dadap red flower can be used as acid-base indicators. Dadap red flowers was macerated using methanol then filtered. The filtrate was ready to use as an acid-base indicator. The extract is tested in an acid-base, buffer solutions, and was compared with phenolphthalein for a strong acid with a strong base while a methyl orange a weak base with a strong acid. Based on the result, indicator of dadap red flower extrat in the strong acid was red colour, while in the weak acid was pink, and also in the strong base was dark green and in the weak base was purple. Furthermore, in the buffer solution, the indicator of dadap red flower extract gave four groups of colour change, namely red color at pH 1 to pH 6, colorless at pH 7 to pH 9, brown at pH 10 and blue at pH 11 to pH 12. Additionally, to attain the end point of titration, the indicators of dadap red flower extract gives a similar results with the comparison indicators. The results showed that the indicator of dadap red flower extracts can be used as an alternative indicator.


2020 ◽  
Vol 12 (2) ◽  
pp. 35
Author(s):  
Sintayehu Leshe ◽  
Habitamu Baye

The use of Acanthus pubescens flower extracts as natural eco-friendly substitutes for synthetic acid - base indicators is experimentally confirmed. In this study, it is indicated that ethanolic and acidified ethanol extracts of Acanthus pubescens flower are good replacements to phenolphthalein, bromothymol blue and methyl red in acid-base titrations involving a strong acid versus strong base and a strong acid versus weak base. They can also be used as effective substitutes to phenolphthalein in a weak acid versus strong base titrations. And also the acidified ethanol extracts can be used in place of phenolphthalein and bromothymol blue while the ethanol extracts can replace methyl red in weak acid versus weak base titrations. It is also concluded that the use of Acanthus pubescens flower extract as an indicator in all types of acid base titrations is beneficial because of its economy, eco-friendly nature, ease of preparation, availability, simplicity, non-carcinogenicity, precision and accuracy of results.


Author(s):  
Prashant Thote

In acid- base titrations, indicators are used to show a sharp color changes at interval of pH.Natural pigments in plants are highly colored substances and may show color changes withvariation of pH. An attempt has been made to investigate the indicator activity of root extract of golden beet root and to replace the synthetic indicators as they have certain disadvantages like chemical pollution, availability problems and high cost.   A study has been done to investigate the indicator activity of aqueous extract of root pigments and compared with that of already existing synthetic indicators. Pigments were extracted using hot water and a definite volume was added which gave accurate and reliable results for all the four different types of neutralization titrations - strong acid against strong base, strong acid against a weak base, weak acid against strong base and weak acid against weak base. The work proved to be acceptable in introducing root pigments as a substitute to the synthetic acid-base indicators.


2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
N. Kapilraj ◽  
S. Keerthanan ◽  
M. Sithambaresan

Commonly used indicators for acid-base titrations are synthetic, and this work was focused to identify the eco-friendly natural indicators and to determine their pKa values. The analytical potential of the flower extracts is very promising as seen in its application in acid-base titrimetry. These selected flower extracts were found to perform well in titrating strong acid-strong base than in weak acid-strong base. We have obtained a sharp and clear colour change from red to brownish yellow for the Bougainvillea glabra extract, from red to yellow for the Bauhinia purpurea extract, and from red to brownish yellow for the Impatiens balsamina extract. All the three flower extracts gave clear colour change with acids and bases, and the colour change was maintained with different acids and bases. The sharp contrast between their colours in acid and base made the pigment suitable for use as acid-base indicators. As these flower extracts have very simple,cost-effective, environment friendly extraction procedure and excellent performance with sharp colour change in end points of the titrations, it would be possible to replace the standard indicators being used in conventional laboratories with natural flower indicators.


2019 ◽  
Author(s):  
Marc Blétry

Henderson-Hasselbalch relation is generally the simplified theoretical framework used to introduce students to acid-base titration. However, it is not always valid and its limitations should be made clear to chemistry students. The appropriate parameter to evaluate its validity is K a /C 0 , in connection with Ostwald dilution law. For more advanced students, it is possible to deduce analytical expressions that always fit accurately acid-base titrations and allow an evaluation of Henderson Hasselbalch relation. Gran plot appears as a particularly sensitive technique to the breakdown of Henderson Hasselbalch relation.


2021 ◽  
Vol 5 (2) ◽  
pp. 15
Author(s):  
Paz Nativ ◽  
Yonatan Gräber ◽  
Yaron Aviezer ◽  
Ori Lahav

A new analytic approach is presented for determining the total volatile fatty acids (VFAT) concentration in anaerobic digesters. The approach relies on external determination of the inorganic carbon concentration (CT) in the analyzed solution, along with two strong-acid titration points. The CT concentration can be determined by either a direct analysis (e.g., by using a TOC device) or by estimating it from the recorded partial pressure of CO2(g) in the biogas (often a routine analysis in anaerobic digesters). The titration is carried out to pH 5.25 and then to pH 4.25. The two titration results are plugged into an alkalinity-mass-based equation and then the two terms are subtracted from each other to yield an equation in which VFAT is the sole unknown (since CT is known and the effect of the total orthophosphate and ammonia concentrations is shown to be small at this pH range). The development of the algorithm and its verification on four anaerobic reactor liquors is presented, on both the raw water and on acetic acid-spiked samples. The results show the method to be both accurate (up to 2.5% of the expected value for VFAT/Alkalinity >0.2) and repetitive when the total orthophosphate and ammonia concentrations are known, and fairly accurate (±5% for VFAT >5 mM) when these are completely neglected. PHREEQC-assisted computation of CT from the knowledge of the partial pressure of CO2(g) in the biogas (and pH, EC and temperature in the liquor) resulted in a very good estimation of the CT value (±3%), indicating that this technique is adequate for the purpose of determining VFAT for alarming operators in case of process deterioration and imminent failure.


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