scholarly journals Green Chemistry: A study on acid-base indicator property of various flower pigments

2018 ◽  
Vol 7 (6) ◽  
pp. 3155-3163
Author(s):  
Lavanya D ◽  
Guna shekhar G ◽  
Purushothom A ◽  
Pallavi A
Keyword(s):  
Green Chemistry ◽  
Acid Base ◽  
Flower Pigments

scholarly journals Green Chemistry Based Interactive Multimedia on Acid-Base Concept

2019 ◽  
Vol 1364 ◽  
pp. 012006
Author(s):  
M. Yustiqvar ◽  
G Gunawan ◽  
S Hadisaputra
Keyword(s):  
Green Chemistry ◽  
Interactive Multimedia ◽  
Acid Base ◽  
Base Concept

The role of green chemistry activities in fostering secondary school students' understanding of acid–base concepts and argumentation skills

2016 ◽  
Vol 17 (4) ◽  
pp. 893-901 ◽  
Author(s):  
Mageswary Karpudewan ◽  
Wolff Michael Roth ◽  
Devananthini Sinniah
Keyword(s):  
Secondary School ◽  
Green Chemistry ◽  
Chemistry Curriculum ◽  
Acid Base ◽  
School Students ◽  
Significant Treatment ◽  
Student Centered ◽  
Base Concept ◽  
Quasi Experimental ◽  
The Individual

In a world where environmental degradation is taking on alarming levels, understanding, and acting to minimize, the individual environmental impact is an important goal for many science educators. In this study, a green chemistry curriculum—combining chemistry experiments with everyday, environmentally friendly substances with a student-centered approach that includes student–student discussion—was tested for its potential to increase the understanding of acid–base concepts and argumentative skills. A quasi-experimental design was chosen intended to take into account teacher/school nested effects. The study involved three classes of 150 16 year old Form Four students (1 experimental,N= 50; 2 control,N= 100) from two Schools A and B serving students from the same sociocultural and economic backgrounds taught by two teachers (Teacher A in School A taught 1 experimental and 1 control; Teacher B in School B taught 1 control). An ANCOVA with a pre-test as a covariate showed a statistically significant treatment effect as measured by an acid–base concept understanding test. Additionally, qualitative analysis of an Argumentation Skill Test (AST) shows that the experimental students used higher levels of argumentation skills following treatment than their peers in the two control classes. Implications are discussed for integrating green chemistry into the secondary school chemistry curriculum to teach the content on acid–base and green chemistry as a tool to assist the construction of arguments.

scholarly journals PENGEMBANGAN LEMBAR KERJA PESERTA DIDIK (LKPD) UNTUK MELATIHKAN KETERAMPILAN PROSES SAINS BERWAWASAN GREEN CHEMISTRY PADA MATERI ASAM BASA

2020 ◽  
Vol 9 (3) ◽  
pp. 280-289
Author(s):  
Suci Lailatul Fitriya ◽  
Mitarlis Mitarlis
Keyword(s):  
Green Chemistry ◽  
Construct Validity ◽  
Base Material ◽  
Process Skills ◽  
Waste Prevention ◽  
Acid Base ◽  
Student Responses ◽  
Science Process Skills ◽  
Student Activities ◽  
Renewable Feedstocks

Penelitian ini bertujuan untuk mendeskripsikan kelayakan LKPD yang dikembangkan untuk melatihkanketerampilan proses sains berwawasan green chemistry pada materi asam basa. LKPD ini disusunberdasarkan komponen keterampilan proses sains, yang dilatihkan yaitu mengamati, membuat hipotesis,merencanaan penelitian, mengklasifikasi, menginterpretasi data dan menyusun kesimpulan. Prinsip greenchemistry pada penelitian ini dibatasi hanya 3 prinsip yaitu prinsip no.1 tentang mencegah/mengurangilimbah, no.7 penggunaan bahan baku yang dapat diperbaharui dan no.12 mencegah/mengurangiterjadinya kecelakaan kerja. Rancangan penelitian ini menggunakan model 4-D (define, design, developdan desseminate) namun, pada penelitian ini hanya dibatasi sampai tahap develop dan dilakukan ujiterbatas terhadap 12 peserta didik kelas XI IPA SMA Negeri 14 Surabaya. Kelayakan LKPD yangdibahas meliputi: 1) validitas yang ditinjau dari validitas isi dan validitas konstruk, 2) kepraktisan yangditinjau dari aktivitas peserta didik dan angket respon peserta didik, serta 3) keefektifan yang ditinjau darites keterampilan proses sains (pretest dan posttest). Hasil penelitian menunjukkan bahwa kelayakanLKPD ditinjau dari validitas isi dikatakan valid dengan persentase 80,36% dan validitas konstruk dalamkategori sangat valid dengan persentase rata-rata keseluruhan 83,89%. Kepraktisan yang ditinjau dariaktivitas peserta didik dan respon peserta didik memperoleh hasil yang sangat praktis dengan presentase90,28% dan 95,49%. Keefektifan yang ditinjau dari hasil tes keterampilan proses sains mendapatkan ngain score berkisar antara 0,66-0,88 dengan kategori sedang-tinggi sehingga pengembangan LKPDdikatakan layak untuk digunakan dalam pembelajaran.Kata kunci: Lembar Kerja Peserta Didik (LKPD), Keterampilan Proses Sains, dan Green Chemistry. AbstractThe aims of this study is describe developed worksheet to practice science process skills oriented greenchemistry on acid base material. This worksheet was arranged based on the components of scienceprocess skills, mainly; doing observation, making hypotheses, planning research, classifying data, andmaking conclutions. The principles of green chemistry in this study were limited to 3 principles such asnumber 1 about waste prevention, number 7 about using of renewable feedstocks, and number 12 aboutconditioning for accident prevention. The design of this study is used a 4-D (define, design, develop anddesseminate), however, this study is only limited to develop and conduct a limited test of 12 students ofclass XI IPA SMA 14 Surabaya. The feasibility of worksheet discussed includes: 1) validity in terms ofcontent validity and construct validity, 2) practicality in terms of student activities and studentquestionnaire responses, and 3) effectivity in terms of science process skills tests (pretest and posttest).The results showed that the feasibility of worksheet in terms of content validity was said to be valid with apercentage of 80.36% and construct validity was said to be very valid with an overall average percentageof 83.89%. Practicality in terms of student activities and student responses obtained very practical resultswith a percentage of 90.28% and 95.49%. The effectiveness in terms of the results of the science processskills test got n-gain score ranging from 0.66-0.88 on the medium-high category so that the developmentof worksheet is feasible use in learning.Key words: Student Worksheet, Science Process Skills, Green Chemistry

scholarly journals PENGEMBANGAN MODUL CONTEXTUAL TEACHING AND LEARNING (CTL) BERORIENTASI GREEN CHEMISTRY UNTUK PERTUMBUHAN LITERASI SAINS SISWA

2016 ◽  
Vol 4 (1) ◽  
pp. 17
Author(s):  
Hari Prima Ahmadi ◽  
Suryati Suryati ◽  
Yusran Khery
Keyword(s):  
High School Students ◽  
Green Chemistry ◽  
Student Attitudes ◽  
Science Literacy ◽  
Evaluation Model ◽  
Average Score ◽  
Design Development ◽  
Acid Base ◽  
School Students ◽  
Science Data

Acid-base is one of topics considered difficult by students. This concept is broad,  varied. Despite it is very closely related to everyday life, its application was still lacking. The development of teaching materials in the form of a module was deemed to be a solution to this problem. The aim of this research was to develop CTL module with green chemistry orientation in acid-base subject material to improve science literacy of students. This study was developed ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model. The developed product was validated by three experts, a practitioner and ten high school students. Data were analyzed using percentage formula. Qualitative data in the form of comments and suggestions from validator were used as consideration to revise the developed module.Tthe effectivity of the module was assessed using N-gain test. Based on validation results, we obtained average of 86,5%, 97%, 88%, and 94,58%. Effectivity evaluation using N-gain test shows an average score of 0,5 with moderate category. Result of student attitudes towards science data has an average score of 74% with good qualifications. It was concluded that developed module prototype is effective for acid-base topic, and most likely for other topics in learning process and growing student science literacy.

scholarly journals Study of acid-base indicator property of flowers of Ipomoea biloba

2012 ◽  
Vol 1 (12) ◽  
pp. 420-422 ◽  
Author(s):  
Sajin Kattuvilakam Abbas
Keyword(s):  
Color Change ◽  
Strong Acid ◽  
Pharmaceutical Journal ◽  
Weak Acid ◽  
Hot Water ◽  
Weak Base ◽  
Acid Base ◽  
Strong Base ◽  
Color Changes ◽  
Flower Pigments

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

Photoinduced Reduction of Nitrobenzenes to Primary Aromatic Amines

Synlett ◽  
2017 ◽  
Vol 28 (10) ◽  
pp. 1191-1194 ◽  
Author(s):  
Gary Chuang ◽  
Hua-Hsuan Huang ◽  
Yu-Feng Chen ◽  
Guang-Hao Niu
Keyword(s):  
Heavy Metals ◽  
Green Chemistry ◽  
Column Chromatography ◽  
Aromatic Amines ◽  
Uv Light ◽  
Broad Band ◽  
Acid Base ◽  
Primary Aromatic Amines ◽  
Electron Withdrawing Substituents

Primary aromatic amines were synthesized from the corresponding nitrobenzenes via photoinduced reduction. The reaction was found to be effective when nitrobenzenes with electron-withdrawing substituents were irradiated with a broad band of UV light centered at 306 nm. When reactions are completed, products could be isolated by acid–base extraction or by column chromatography. This presenting photoreaction procedure for the synthesis of primary aromatic amines from the corresponding nitrobenzenes proceeds without the need of a sensitizer in isopropanol or THF. Without the usage of catalysts, or stoichiometric reducing reagent containing heavy metals, this photoinduced reduction of nitrobenzenes fulfils the concept of green chemistry.

scholarly journals Rosa sp and Hibiscus sabdariffa L extract in ethanol fraction as acid base indicator: Application of green chemistry in education

2019 ◽  
Vol 1402 ◽  
pp. 055041
Author(s):  
M Paristiowati ◽  
M Moersilah ◽  
M M Stephanie ◽  
Z Zulmanelis ◽  
R Idroes ◽  
...  
Keyword(s):  
Green Chemistry ◽  
Hibiscus Sabdariffa ◽  
Acid Base ◽  
Ethanol Fraction

scholarly journals Rosa sp and Hibiscus sabdariffa L Extract in Ethanol Fraction as Acid Base Indicator: Application of Green Chemistry in Education

2019 ◽  
Author(s):  
Nur Tsalits Fahman Mughni
Keyword(s):  
Green Chemistry ◽  
Raw Material ◽  
Hazardous Wastes ◽  
Hibiscus Sabdariffa ◽  
Acid Base ◽  
Renewable Materials ◽  
Chemistry Learning ◽  
Chemical Products ◽  
Method Of Extraction ◽  
Ethanol Fraction

Green Chemistry principal was introduced in an academic environment in the 1980s as guidelines for sustainable development focused on chemistry. Efforts to realize these expectations can be applied through education by developing learning process based on environmental. This study aims to apply the concept of Green Chemistry in education, especially chemistry learning by producing natural acid-base indicators from the extract of roses (Rosa sp) and Rosella (Hibiscus sabdariffa L). These indicators are produced by the method of extraction using 96% ethanol solvent in an acidic atmosphere at pH 3-4. The results of maceration then extracted in three different solvents (ethanol, n-hexane, and chloroform). The extract was tested in solution with pH 1-12 and used as an indicator to identify the solutions and titration in acid-base topic. It concluded that the roses and Rosella can be used as an alternative raw material for acid base indicator. The use of roses and Rosella indicates an attempt to have applied the principles of green chemistry, including the prevention of the formation of hazardous wastes, the design of safe chemical products, the use of renewable materials, the design of materials that are easily degraded, and the use of safe solvents.

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