Kinetika Adsorpsi Ion Emas(iii) Oleh Hibrida Merkapto Silika

: Adsorption kinetics study has been done of gold(III) ions by mercapto silica hybrid (MSH) adsorben. MSH was synthesized by sol-gel process with sodium silicate (Na2SiO3) from rice husk ash as a precursor. MSH made by adding hydrochloric acid to 3-(trimetoksilil)-1-propantiol (TMSP) compounds and Na2SiO3 solution. Adsorption kinetics are determined by adsorption static system (batch) with variation of time. The amount of the adsorbed gold ions is quantified by the difference in metal concentration before and after adsorption analyzed by atomic absorption spectroscopy (AAS). The data showed, MSH interaction with gold ion tends to follow the pattern of reaction kinetics pseudo-second-order with rate constant (k) =1x10-2 g mg-1min-1. Based on the value of the standard Gibbs free energy for adsorption (-ΔG°= 34,63-37,99 kJ/mol) showed that the adsorption takes place chemically (chemisorption)

Praktikum Kimia Berbasis Kimia Komputasi Untuk Sekolah Menengah Atas

Program pengembangan praktikum kimia berbasis kimia komputasi untuk Sekolah Menengah Atas telah dilaksanakan pada kelompok kerja guru kimia mitra (SMAN 1 Narmada dan SMAN 2 Narmada) di Kabuaten Lombok Barat, Indonesia. Kegiatan dilaksanakan dengan dengan mengadopsi langkah-langkah penelitian tindakan yang terdiri dari empat tahapan, yaitu: perencanaan, tindakan, observasi dan evaluasi, dan refleksi. Target yang telah dicapai melalui kegiatan ini adalah 1) Teridentifikasinya konsep-konsep kimia SMA yang esensial yang bisa diajarkan dengan lebih mudah bila melibatkan eksperimen berbasis kimia komputasi sebagai alternatif pengganti praktikum di laboratorium. 2) Teridentifikasinya perangkat lunak yang dapat digunakan oleh guru sebagai alternative pengganti praktikum kimia. 3) Mengukur tingkat motivasi guru sebelum dan setelah kegiatan untuk melaksanakan praktikum kimia di sekolah. 4) Adanya produk berupa buku panduan praktikum kimia SMA berbasis kimia komputasi yang dapat digunakan sebagai alternatif pengganti praktikum di laboratorium. Program ini sangat berguna untuk meningkatkan proses belajar mengajar kimia di sekolah

Optimasi Sifat Inhibitor Korosi Senyawa Thiaamida-pirazolindol Berdasarkan Teori Fungsional Kerapatan

. Corrosion inhibitor properties of thiamide pyrazolindole and its derivatives has been elucidated by means of density functional theory (DFT) at B3LYP/6-31G(d) level of theory. Effect of electron donating and withdrawing groups such as NH2, SH, CHCH2, CH3, OH, CHO, COOH, F and NO2 on the corrosion inhibitor of thiamide pyrazolindole derivatives also have been studied. The quantum chemical parameters such as the frontier orbital energies (EHOMO), ionization potential (I), electron affinity (A) and electronegativity (χ) are closely related to the corrosion inhibition efficiency (IE%) of thiamide pyrazolindole derivatives. The presence of electron donating groups increases IE% values meanwhile electron withdrawing groups reduce IE% values. The enhancement of IE% follows NO2 < CHO < COOH < SH < F < CH3 < CHCH2 < OH < NH2. Electron donating NH2 group gives 98,76 % of IE%, pure thiamide pyrazolindol IE% = 90,80 %. In contrast, electron withdrawing NO2 group gives IE% only 82,82 %. This theoretical study would have a significant contribution in designing high-efficiency organic corrosion inhibitors

Alat Destilasi Sederhana Sebagai Media Edukasi Untuk Meningkatkan Minat Wirausaha Siswa-siswi SMA IT Al Kamal Nw Narmada

: Improvement of human resources faces many challenges, especially in terms of facilities and infrastructure, especially for private schools in rural, West Lombok. One of the high schools that face the same problem is the High School IT Al Kamal NW Narmada located in the village ofGolong District of Narmada, Lombok Barat. School was established in 2008 but have no adequate classroom facilities and laboratory equipment. It is very difficult for students to understand science concepts in more depth without laboratory work activity. Therefore it needs innovation for simple laboratory work activity by utilizing second-hand goods that readilyavailable. The simple innovation that has been introduced is to design and manufacture simple distillation apparatus in order to help students understand the concept of distillation and its application in the industry. This approach is expected to increase creativity and interest of the student especially from SMA IT Al Kamal to develop simple destilation apparatus for practical purposes (e.g in agriculture) so that it is espected that student has entrepreneurs skills