Deskripsi Kemampuan Psikomotorik Mahasiswa Pendidikan Kimia pada Titrasi Asam Basa

The background of this research is the need to know the ability of Chemistry Education students, who would be chemistry teacher in the future, in using laboratory equipments, especially in acid-base titration. This study aims to describe the psychomotor ability of Chemistry Education students in acid-base titration. The research method used is descriptive with the instrument which is observation sheet and interview guide. The analyses result shows that the average psychomotor ability of Chemistry Education students is 82.16%, which is categorized as very well. These skills include assembling titration tools which is categorized well with an average percentage of 76.38%, pouring NaOH solution into the burette which is categorized very well with an average percentage of 81.94%, taking the solution which is going to be analyzed into the Erlenmeyer flask which is categorized well with an average percentage of 77.78%, conducting titration which is categorized very well with the average percentage of 86.11%, observing the volume of titrant and the color of analyte which is categorized as enough with average percentage of 60.41%.

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

Jurnal Akademika Kimia ◽

10.22487/j24775185.2020.v9.i1.pp7-15 ◽

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).

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Effect of Amphoteric Zn2+ on the Determination of B2O3 Content in Glass

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.680.289 ◽

2016 ◽

Vol 680 ◽

pp. 289-292

Author(s):

Yong Zhi Bai ◽

Hong Yan Guan ◽

Jin Hua Cui

Keyword(s):

Borosilicate Glass ◽

Ph Value ◽

Precipitation Method ◽

Acid Base ◽

Standard Substance ◽

Acid Base Titration ◽

Naoh Solution ◽

Verification Test ◽

Optimal Ph

The amphoteric ZnO can affect the titration of B2O3 content in glass since the Zn2+ will react with standard NaOH solution during the acid-base titration process and the result will be slightly higher sequentially. In this paper, the elimination of amphoteric Zn2+ was carried out by means of carbonate and Zn (OH)2 precipitation method. Results show that the optimal pH value for Zn (OH)2 precipitation is between 9~10. Verification test under borosilicate glass standard substance indicates that this method shows great applicability and accuracy in the determination of B2O3 content in Zn containing glass.

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Miskonsepsi Asam Basa Berbasis Multipel Representasi pada Lintas Jenjang Pendidikan

Jurnal Pendidikan: Teori, Penelitian, dan Pengembangan ◽

10.17977/jptpp.v4i12.13082 ◽

2019 ◽

Vol 4 (12) ◽

pp. 1635

Author(s):

Isnaini Yunitasari ◽

Hayuni Retno Widarti ◽

Nazriati Nazriati

Keyword(s):

Diagnostic Tests ◽

Research Method ◽

Descriptive Analysis ◽

Research Subjects ◽

Acid Base ◽

Quantitative Descriptive Analysis ◽

Multiple Representation ◽

Average Percentage ◽

Analysis Process ◽

Quantitative Descriptive

<pre>Abstract: This study aims to describe acid-base misconceptions across levels of education using multiple representation based diagnostic tests. The research method is quantitative descriptive. Analysis process of misconceptions using modified CRI. The validity of diagnostic tests is between 0.197 to 0.798, and reliability is 0.753 and 0.626. The research subjects were 224 people consisting of class XI students, class XII students, second semester students, and 4</pre>th<pre> semester students. The results showed that the average percentage of acid-base misconceptions in class XI students to 4th semester students respectively was 50.30%; 56.84%; 53.81%; and 41.07%. Misconceptions that often occur in students and students related submicroscopic representations.</pre><pre> </pre>Abstrak: Penelitian ini bertujuan untuk mendeskripsikan miskonsepsi asam basa pada lintas jenjang pendidikan menggunakan tes diagnostik berbasis multipel representasi. Metode penelitian adalah deskriptif kuantitatif. Cara analisis miskonsepsi menggunakan CRI termodifikasi. Validitas tes diagnostik antara 0,197 hingga 0,798, dan reliabilitas sebesar 0,753 dan 0,626. Subjek penelitian sebanyak 224 orang yang terdiri dari siswa kelas XI, siswa kelas XII, mahasiswa semester II, dan IV. Hasil penelitian menunjukkan rata-rata persentase miskonsepsi asam basa pada siswa kelas XI hingga mahasiswa semester IV secara berurutan adalah 50,30%; 56,84%; 53,81%; 41,07%. Miskonsepsi yang sering terjadi pada siswa dan mahasiswa terkait representasi submikroskopik.

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The possibility of determining the activity coefficients of individual ions from acid-base titration data

Journal de Chimie Physique ◽

10.1051/jcp:1998330 ◽

1998 ◽

Vol 95 (7) ◽

pp. 1583-1605 ◽

Cited By ~ 2

Author(s):

I. Jano ◽

J. E. Hardcastle

Keyword(s):

Activity Coefficients ◽

Acid Base ◽

Acid Base Titration ◽

Titration Data

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Chemical composition determination of some polyphosphonic acids and their corresponding salts by acid-base titration coupled with a computer simulation. Acidity constants evaluation.

European journal of water quality ◽

10.1051/wqual/2006004 ◽

2006 ◽

Vol 37 (2) ◽

pp. 189-201 ◽

Cited By ~ 1

Author(s):

F. Nguyen ◽

F. Hui

Keyword(s):

Computer Simulation ◽

Chemical Composition ◽

Acid Base ◽

Acidity Constants ◽

Composition Determination ◽

Acid Base Titration

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Henderson Hasselbalch Relationship and Weak Acid Titration

10.26434/chemrxiv.8256035.v1 ◽

2019 ◽

Author(s):

Marc Blétry

Keyword(s):

Theoretical Framework ◽

Weak Acid ◽

Acid Base ◽

Sensitive Technique ◽

Chemistry Students ◽

Advanced Students ◽

Acid Titration ◽

Acid Base Titration ◽

Analytical Expressions

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.

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Direct Synthesis of 3,5-Dinitropyrazole Catalyzed by Newly Sulfated Nanosolid Superacid TiO2/ SO

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.391-392.1296 ◽

2011 ◽

Vol 391-392 ◽

pp. 1296-1301

Author(s):

Li Min Xi ◽

Xin Xin Zhang

Keyword(s):

Direct Synthesis ◽

Sol Gel ◽

Acid Base ◽

Direct Transformation ◽

Acid Base Titration ◽

Optimal Reaction Condition ◽

Superacid Catalyst ◽

Average Size ◽

Optimal Reaction ◽

Xrd And Tem

The newly sulfated nanosolid superacid TiO2/SO4 prepared by sol-gel method was broadly characterized by acid base titration, XRD and TEM, which identified that the superfine solid TiO2/SO4 showing good dispersibility with average size of 27 nm belongs to kind of crystalline nanoparticles. With the help of the catalyst TiO2/SO4, the optimal reaction condition for direct transformation of pyrazole and nitrosonitric acid into 3, 5-Dinitropyrazole was n (pyrazol)=0.10 mol, m (TiO2/SO4 )＝1.5g, V(n-octannol)＝90mL, and V(nitrosonitric acid)＝50mL. Moreover, the optimal yield of the catalytic reaction reached up to 59.4% when the reaction time is 7 hours. The nanosolid superacid catalyst is still of high activity after regenerating eight times by calcination at 600。C.

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