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The research aims to determine the effect of learning style on students’ performance through online learning during the Covid-19 pandemic. The subjects of study are 269 chemistry education students at three universities in Indonesia. The data collection of learning style uses a Likert scale questionnaire, and learning performance is obtained from students’ grade point average. In this research, students’ learning style was divided into visual, auditorial, and kinesthetic. Data were analyzed using descriptive statistics with linear regression and ANOVA tests. The learning styles positively affect student learning performance by 4.7%, while 95.3% of other factors are not examined in this study. The learning performance of students with auditory is higher than visual and kinesthetic learning styles. Based on the inferential analysis, there is no significant difference in student learning performance based on student learning styles. Therefore, students with different learning styles have the same learning performance in online learning.

One of the most well-known material for lithium battery cathode synthesis of lithium ferro-phosphate type is iron phosphate precursor. The precursor is synthesized by the use of leaching method with tartaric acid solution with optimization at various leaching temperature and time. The temperature variables are at 30 ℃, 50 ℃, 70 ℃, and 90 ^oC. The time variables are at 3 hours, 6 hours, and 9 hours. The main material that is used is iron from used nickel plated A3 steel battery shell. The recovered iron concentration and quantity is calculated from absorbance by atomic absorption spectrophotometry (AAS). AAS analysis indicates the absorbed Fe is rated at 1,02 % (30 ℃, 2,76 % (50 ℃), 9,93 % (70 ℃), and 34,31 % (90 ℃) during 9 hours of leaching.The analysis indicates the recovered iron is rated the highest during 9 hours of leaching at the highest temperature. X-ray diffraction analysis at various leaching temperature variable indicates formation of iron phosphate crystal to be compared with iron phosphate commercial precursor, while scanning electron microscope analysis shows uniform iron phosphate particle morphology.

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Tujuan penelitian ini untuk menganalisis kemampuan mahasiswa dalam menggunakan Lembar Kerja Mahasiswa (LKM) berbasis Problem Based Learning (PBL) pada penentuan kadar asam palmitat bebas dalam minyak goreng dan menganalisis keterampilan proses sains. Metode penelitian yang digunakan adalah penelitian kelas pada mahasiswa mata kuliah kimia bahan makanan sebanyak 38 orang. Data diperoleh dari jawaban mahasiswa dalam menyelesaikan setiap tahapan LKM yang diberikan, sedangkan keterampilan proses sains didapat dari jawaban siswa pada LKM yang disesuaikan dengan indikator ketrampilan proses sains. Kemampuan mahasiswa dalam menyelesaikan LKM diinterpretasikan sebagai berikut : fase “orientasi pada masalah” baik (70.3), fase”belajar mandiri’ baik (76.0), fase ”penyelidikan” baik sekali (94.3), fase ”penyajian data” baik (72.7) dan fase “evaluasi hasil kerja” baik (72.4). Keterampilan proses sains mahasiswa secara keseluruhan diinterpretasikan baik dengan rata-rata 75.6, dengan perolehan nilai pada indikator mengamati 88.9, mengajukan pertanyaan 70.3, mengajukan hipotesis 70.8, menerapkan konsep 75.6, merancang percobaan 91,6, menyimpulkan 67.3 dan mengomunikasikan 73.1