scholarly journals NEW ACID-BASIC INDICATORS: RESEARCH USING A SMARTPHONE

2021 ◽  
Vol 26 (1(77)) ◽  
pp. 97-106
Author(s):  
A. P. Avdeenko ◽  
Yu. P. Holmovoj ◽  
S. A. Konovalova ◽  
I. Yu. Yakymenko
Keyword(s):  
Computer Software ◽  
Glass Electrode ◽  
Acid Base ◽  
Color Transition ◽  
Color Characteristics ◽  
Wide Range ◽  
Acid Base Titration ◽  
Ph Range ◽  
Rgb Model

Modern cameras, desktop scanners, smartphones allow not only registering an image, but also determining its color characteristics. That allows us to quickly, objectively and automatically determine the color characteristics of colored samples in acid-base titration, because there is a significant error at visually determining the pH range of the color transition. In analytical chemistry the characteristics of acid-base indicators are very important, in particular their pH transition interval. But the disadvantage of most indicators is the wide range of color transition: from 1 to 3 pH units. The aim of this work is to find new acid-base indicators that change color in an alkaline environment and have a narrow pH range of the color transition. We have developed the apparatus and technique of convenient and highprecision simultaneous determination of the pH of the medium and the color of the acidbase indicators. In acid-base titration the PH measurements were performed with a combined glass electrode AD1131 by рН-meter AD1000. The color transition was determined with help of a smartphone with the subsequent processing of the results by computer software. The color characteristics were measured for each channel of the RGB model in the range from 0 to 255. Our apparatus is small and mobile, and allows us simultaneously to measure the pH of the medium and accurately to determine the color characteristics. As a result, we can construct graphical dependencies of color on pH for each channel of the RGB model. We found the N-arylsulfonyl-2-aroylamido-1,4-benzo(naphto)quinone monoimines and 2,5-dibenzoylamido-1,4-benzoquinone are good acid-base indicators. They “work” in the pH range from 8.82 to 11.35 and have a very narrow color transition interval from 0.10 to 0.61. Solutions of these compounds in an alkaline medium have bright intense colors due to formation of mesomeric ions. That allows using of these indicators in the titration of weak acids with strong bases and vice versa by the method of neutralization.

scholarly journals USING POTENTIOMETRIC ACID-BASE TITRATION TO DETERMINE PKA FROM MANGOSTEEN PERICARPS EXTRACT

2019 ◽  
Vol 16 (32) ◽  
pp. 768-773
Author(s):  
L. TANIA ◽  
C. DIAWATI ◽  
M. SETYARINI ◽  
N. KADARITNA ◽  
A. SAPUTRA
Keyword(s):  
Oxalic Acid ◽  
Potentiometric Titration ◽  
Accurate Determination ◽  
Acidity Constant ◽  
Equivalence Point ◽  
Acid Base ◽  
Titrant Volume ◽  
Acid Base Titration ◽  
Ph Range

One of the uses of acid-base indicators is to show the end point of the titration, so the accurate determination of acidity constant and pH range of indicators needs to be done. This study aims to determine the acidity constant (pKa) of mangosteen pericarp extract and its accuracy as an indicator of acid-base titration. Determination of pKa was done by a simple potentiometric titration method. The titration data were plotted in three graphs, i.e., pH, ΔpH/ΔV (the (the first derivative), and Δ2pH/ΔV2 (the second derivative) versus titrant volume to determine the equivalence point of the titration. The accuracy test was carried out by comparing the volume of oxalic acid used to titrate NaOH solution using the indicator of mangosteen pericarp extract and phenolphthalein indicator. The result showed that the equivalence point was found on the titrant volume of 8.6 mL and a measured pH of 9.84. so the pKa value of mangosteen pericarp extract was 7.20, and the pH range was 6.20 to 8.20. the average volume of oxalic acid used to titrate 5 mL of NaOH using phenolphthalein as the indicator was 5.2 mL while the titration used mangosteen pericarp extract was 5.23 mL. The accuracy of mangosteen pericarp extract was 99.42%. By the result, it can be concluded that potentiometric titration can be used as a simple way to determine the acidity constant of mangosteen pericarp extract. Moreover, the mangosteen pericarp extract can be used as an alternative acid-base titration indicator to substitute the common acid-base titration in the laboratory.

scholarly journals Utilization of Extract of Sambang Getih Leaves (Hemigraphis colorata. Hall. F) as a Acid-Base Indicator

2020 ◽  
Vol 9 (1) ◽  
pp. 7-15
Author(s):  
Eksari Ekasari ◽  
Purnama Ningsih
Keyword(s):  
Leaf Extract ◽  
Strong Acid ◽  
Weak Base ◽  
Acid Base ◽  
Strong Base ◽  
Unique Color ◽  
Acid Base Titration ◽  
Naoh Solution ◽  
Ph Range ◽  
Color Pigment

Getih sambang leaves (Hemigraphis Colorata. Hall. F) are plants that have a distinctive and unique color, namely the upper surface of the leaf is green and the bottom of the leaf is burgundy where sambang leaves contain anthocyanin compounds. Anthocyanin is the color pigment in plants that forms the basis of the use of natural indicators. This study aims to prove whether getih cucumber leaves can be used as an acid-base indicator, to determine the type of acid-base titration that is suitable for indicators of getih cucumber leaves, and to find out what the pH-changing color route of getih cucumber leaves is. The method used is extraction, namely maceration. Wee leaves are macerated by using methanol as a solvent for 24 hours. The extract was previously tested using HCl solution and NaOH solution as a test to prove the presence of anthocyanin. The results obtained in this study, getih sambang leaf extract can be used as an indicator of acid base, and also the type of acid-base titration that is suitable for use in the indicator of getih leaf extract extract precisely on the titration of strong-base strong acid, and strong weak base-acid It is best used as a substitute for the phenolphthalein indicator. In titration of strong and weak acids and bases, it is good to be used as a substitute for the indicator of methyl orange. The pH range obtained from the getih sambang leaf extract is pH 4-7 (red-purple).

Influence of temperature on blood pH of the human adult and newborn

1964 ◽  
Vol 19 (5) ◽  
pp. 897-900 ◽  
Author(s):  
Karlis Adamsons ◽  
Salha S. Daniel ◽  
Gillian Gandy ◽  
L. Stanley James
Keyword(s):  
Cell Concentration ◽  
Effect Of Temperature ◽  
Red Cell ◽  
Acid Base ◽  
Blood Ph ◽  
Influence Of Temperature On ◽  
The Mean ◽  
Ph Range ◽  
Two Populations

The effect of temperature upon pH of blood from adult and newborn humans was investigated. Although the mean ΔpH/ΔT values for the two populations differed, 0.0144/ °C for adults versus 0.0128 for the newborn, this was not peculiar to the source since the temperature-induced pH changes were identical when comparison was made between samples of similar pH and CO2 content. It was shown that even over the physiologic pH range ΔpH/ΔT is not constant but is a function of pH and CO2. No significant changes in ΔpH/ΔT were observed with oxygenation of hemoglobin. The influence of red cell concentration was detectable only when hematocrit values fell below 20%. A graph and an equation for the determination of ΔpH/ΔT of blood with a given pH and CO2 content is presented. acid base Submitted on December 9, 1963

scholarly journals Comparison of Color Change to pH Range and Acid-Base Titration Indicator Precision Test of Multiple Ethanol Extracts

2021 ◽  
Vol 19 (1) ◽  
pp. 1446
Author(s):  
Lilis Tuslinah ◽  
Anna Yuliana ◽  
Dian Arisnawati ◽  
Lina Rahmawati Rizkuloh
Keyword(s):  
Color Change ◽  
Secondary Data ◽  
Ethanol Extract ◽  
Acid Base ◽  
Color Changes ◽  
Synthetic Indicators ◽  
Significant Difference ◽  
Acid Base Titration ◽  
Ethanol Extracts ◽  
Ph Range

Natural indicators using anthocyanin compounds can be an alternative to synthetic indicators on acid-base titration because anthocyanin is an organic compound that is unstable with changes in pH. The extraction was carried out with ethanol because the compounds of anthocyanin were polar. This study was to ensure an ethanol extract of some plants could be used as an acid-base indicator that had a pH range of color change and the value of the equality parameter was not significantly different from the phenolphthalein indicator. The research method is to collect research journals on making natural indicators from ethanol extracts of various plants compared to phenolphthalein indicators so that secondary data from these journals can be processed statistically. Research results and conclusions: Based on the results of statistical data processing using the t-test there was no difference in the average pH of the phenolphthalein indicator with the average pH of ethanol extracts of adam air leaves (Rheo discolor), white frangipani flowers and Clitoria teratea L., with a significance value > 0.05 and the equality test (precision) had the requirements of good equality. HIGHLIGHTS Natural indicators are needed as a substitute for synthetic indicators in determining acid-base titrations; one of them is anthocyanin dye Research journals on making natural indicators from ethanol extracts of various plants compared to phenolphthalein indicators so that secondary data from these journals can be processed statistically There was no significant difference between the average pH of the phenolphthalein indicator and the average pH of the ethanol extract of Adam's Eve Leaves, ethanol extracts of white Cambodia flowers and ethanol extracts of Telang flowers in producing color changes GRAPHICAL ABSTRACT

Determination Methods of Dialdehyde Celluloses from Bacterial Cellulose

2007 ◽  
Vol 361-363 ◽  
pp. 507-510
Author(s):  
Yu Hong Feng ◽  
Jia Cheng Li ◽  
Qiang Lin ◽  
Su Juan Pang ◽  
Meng Ying Zhang ◽  
...  
Keyword(s):  
Bacterial Cellulose ◽  
Amino Nitrogen ◽  
Aldehyde Group ◽  
Acid Base ◽  
Titration Method ◽  
Cannizzaro Reaction ◽  
Acid Base Titration ◽  
Determination Methods ◽  
Oxidation System

This paper addresses the determination of aldehyde group (% of dialdehyde units) in dialdehyde cellulose (DACs) oxidized from bacterial cellulose (BC). With 4 determination methods, the oxidation degrees of DACs were studied: Automatic potential titration method through Schiff base reaction, Acid-base titration in Cannizzaro reaction, Metaperiodate consumption determination, and Measurement of amino nitrogen content in DAC derivatives. By comparing determination results of these methods, we found out the proper way suitable for this metaperiodate oxidation system of BC to measure the dialdehyde unit content of the DACs.

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