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Cage plants (Canavalia virosa) are classified as nuts. This study aims to prove the flowers of the cage plants as acid-base indicators and determine the type of acid-base titration that is suitable for indicators of cage plants. The flowers of the cage plants were macerated with ethanol. Extras were tested as indicators in acid-base solutions, buffer solutions, and compared with phenolphthalein and methyl orange for acid-base titration, namely: strong acid with a strong base, a weak acid with a strong base, and weak base with strong acid. The results obtained in this study, namely: flower extracts of cage plants in strong red acid, in weak acid pink, in strong green bases, and weak bases in light green. In a buffer solution of pH 1 to pH 11, the flower extract of the cage plants gives 4 color groups, namely: a buffer solution with pH 1 colored red, pH 3 colored pink, pH 5 to pH 9 being light green, and pH 11 being dark blue. Cage plant flower extract can be used as an indicator of acid-base, cage plant flower extract can be used on strong-base strong acid titration, strong weak-acid base, and weak-strong base acid titration.

The topic of buffer has connections between concepts and some prerequisite materials that students should understand to be able to facilitate this material. The lack of mastery on the material will lower the learning outcomes. This study aimed to improve students’ learning outcomes on buffer through the implementation of advance organizer learning model based on numbered heads together (NHT). This study was one group pretest-posttest design. The sample of this study was students of 11th grade Science at SMAN 2 Balaesang consisting of class XI Science 1 as the experiment class 1 with 33 students and class XI Science 2 as the experiment class 2 with 32 students. The effectiveness of the implementation of advance organizer learning model NHT-based can be seen from the average N-gain value of the experimental classes. The average N-gain value of experimental class 1 was 0.69 included in the medium category. While the average N-gain value of experimental class 2 was 0.71 included in the high category. Data analysis showed that the average value of students learning scores was greater than 65, where for the experimental class 1 was 76.36 and the experimental class 2 was 76.71. The advance organizer learning model NHT-based improved learning outcomes of students in 11th grade Science on buffer at SMAN 2 Balaesang.

The red onion of Palu valley variety is a plant that is widely found in Palu area and regarded as a leading commodity in Central Sulawesi. The purpose of this study was to examine the secondary metabolite compounds contained in red onion (Allium ascolinicum L.) of Palu valley variety and its antioxidant activity. Antioxidant activity test in this study used DPPH (1,1-Diphenyl-2-Pikrilhidrazil) as a source of free radical, and vitamin C as the comparison. The antioxidant activity of red onion extract was analyzed using a UV-Vis spectrophotometer. The red onion tuber powder was extracted by maceration using ethanol solvent. Qualitative test of onion powder showed positive results on alkaloids, flavonoids, and tannin compounds. The samples and vitamin C were tested for antioxidant activity in various extract concentrations of 10, 30, 50, 70, and 90 ppm. The results showed that red onion extract of Palu valley variety presented an IC50 value of 38.548 ppm, and vitamin C presented an IC50 value of 22.646 ppm. Based on these values, the red onion (Allium ascolinicum L.) extract is categorized as a very strong class of antioxidant which can be used as a source of natural antioxidant.

This research method was research and development (R & D), which purposed to obtain the sparkol videoscribe designs of colloidal material and the validity of designs that were reviewed by experts as theoretical experts. The object of this study was sparkol videoscribe. Data collection was divided into two, namely media design data and media validity that were designed by using assessment sheets from 5 experts, 3 people were the learning media experts and 2 people were the chemical material experts. Data were analyzed descriptively to determine the justification of the validity of the research object. The results of the data analysis obtained that sparkol videoscribe design of material colloid had characteristics, namely images, moving hand animation, music, explanation of material in the form of sound and the composition of sentences incorporated in whiteboard animation. The designs were declared valid with a very good category according to experts and can be used as a chemistry education media with a score of 3.7 based on the total score of the instructional media experts and 3.45 based on the total score of the chemical material experts.

Improper of usage and storage of cooking oil can increase the water content on cooking oil. It can decrease of cooking oil quality and fried food that resulted from this cooking oil which then can cause health problems. This study aimed to determine of the waste cooking oil quality after it was adsorbed with charcoal from eggshell palm oil (Elaeis gunieensis). The quality was determined based on the free fatty acids, the peroxide value, and the water content of the waste cooking oil before and after adsorption. Determination of free fatty acids was used titration method while determination of water content was used gravimetric method. The result showed that the cooking oil quality contained 0.014% of free fatty acids, 1 meq.O2/kg of peroxide value, and 0.0003% of water content. The waste cooking oil quality without adsorption process was 0.042% of free fatty acids, 26 meq.O2/kg of peroxide value, and 0.0011% of water content. After adsorption process with 5, 10, 15, 20, and 25 gram of charcoal from eggshell palm oil into 100 mL of waste cooking oil, it was found that 15 gram of eggshell weight was the best adsorbent. In was condition, the free fatty acid was 0.0006%, the peroxide value was 2 meq.O2/kg, and the water content 0.0005%. It showed that the waste cooking oil quality become better after adding of charcoal of eggshell palm oil as the adsorbent.

The aim of this study is determine the IC50 extracts values of white peel and flesh of red watermelon, white peel and flesh of yellow watermelon as antioxidants. To determine antioxidant activities DPPH reagent was used as well as UV-Vis Spectrophotometry was used to measure vitamin C as a positive control measurement. The samples mixed with ethanol in various concentration of 5, 15, 25 and 35 mg/L. The results showed that the IC50 values for each extract of red watermelon flesh, yellow watermelon flesh, white peel of red watermelon, and white peel of yellow watermelon were 16.619 mg/L, 16.575 mg/L, 14.729 mg/L, and 16.782 mg/L, respectively. Vitamin C as the positive control has IC50 value of 9.526 mg/L. These IC50 values showed that vitamin C had higher antioxidant activity than watermelon extracts, but the extracts of watermelon still categorized in strong natural antioxidants. This study concluded that watermelon is good to be consumed because it is a very strong antioxidant.

Rosella is one of the plants that has many benefits as well as nutrients used potentially as food ingredients such as jelly candy. Jelly candy was made by mixing rosella flower extracts with a gelling agent. This study aimed to determine the effect of the addition of gelatin from milkfish bones toward the production of jelly from rosella flowers and to determine the addition concentration of gelatin from milkfish bones to obtain a good quality of jelly candy. The gelling agent used was gelatin derived from milkfish bones. Gelatin from milkfish bones was made through several stages i.e. degreasing, demineralization, extraction, and drying then applied to produce jelly candy. Rosella flower was extracted using the infusion method at a temperature of 70 oC. The addition concentration of gelatin varied of 10, 12, 14, 16 18, and 20%. Parameters used were water content and organoleptic test covering of color, aroma, flavor, and texture. Results showed that addition of gelatin from milkfish bones influenced strongly on the moisture content, color, aroma, flavor, and texture of the jelly candy. The good quality of rosella jelly candy was obtained by addition concentration of gelatin of 18% with a water content of 8.76%, and the elasticity was preferred by the panelists.

Research on the effect of the problem-based learning model in the basic laws of chemistry on student’s learning outcomes in class X MAN 2 Model Palu has been done. This study aimed to determine the effect of the application of the problem-based learning model in the basic laws of chemistry on student’s learning outcomes in class X MAN 2 Model Palu. The type of research was a quasi-experimental study non-randomized design with pretest-posttest control group design. The sample was conducted with a purposive sampling technique. The study sample was students in class X MIA 6 as an experimental group (n = 22) and students in class X MIA 3 as a control group (n = 22). The data testing of students' learning outcomes used a non-parametric statistical analysis, the analysis of Mann-Whitney U-Test. The research results indicated that the mean value of the experiment class was high compared to the control class, 22.61 >18.39. The statistical analysis obtained that sig. 2-tailed (0,032) ˂ 0.05 and Zcalculation (-2.149) ˂ Ztable (-1.96). The average value of the experiment class was 82.95 while the average value of the control class was 73.64. So it can be concluded that there is the effect of applying the problem-based learning model in the basic laws of chemistry on student’s learning outcomes.

Salak seed is a waste of salak fruit that contains a high carbohydrate, therefore it can be used as an alternative raw material for the production of bioethanol. The study aims to determine the optimum time of fermentation to produce the highest content of bioethanol and to determine the weight ratio of the yeast and the substrate that produce the highest content of bioethanol. Variations of yeast mass used was 2, 4, and 6 grams and fermentation time were 24, 48, 72, 96, 120, and 144 hours. The analysis showed that the highest content of bioethanol produced was 6 grams of the yeast mass, the fermentation time was 48 hours and the weight ratio of yeast to the substrate was 6: 10 that obtained 11.2%.

Banana peel waste utilization as organic manure and its application has been made to the land kale plant growth (Ipomea reptans Poir). This paper aims to describe how to manufacture liquid organic fertilizer from the waste banana skin, determine the total nitrogen content of liquid organic fertilizer and the effect of liquid organic fertilizer waste banana skin on plant growth kale land (Ipomea reptans Poir). The method used was experimental at the stage of making a liquid organic fertilizer waste banana peel in fermentation, the determination of total nitrogen content and the application of the organic liquid fertilizer waste banana skin using a randomized block design (RBD) with 4 treatments include P0 (0 mL); P1 (20 mL); P2 (40 mL); and P3 (60 mL).The parameters measured were plant height (cm), the number of leaves (leaf) and wet weight (g). The growth data of the swamp cabbage land (Ipomea reptans poir) were analyzed by using the statistical test analysis of variance (ANOVA) then followed by Duncan test with significance level of 5%. The results showed that levels of total nitrogen of the organic liquid fertilizer waste was 0.032% and the application of the organic liquid fertilizer of banana peel waste on the growth of swamp cabbange land (Ipomea reptans poir) influence on plant height (cm) and wet weight (g) but have no effect on the number of leaves (leaf). Treatment P2 (40 mL) showed the best result for the average plant height (cm), the number of leaves (leaf) and wet weight (g) of the swamp cabbage land (Ipomea reptans poir).

This study aimed to determine the optimum pH and the optimum weight of charcoal and activated charcoal from water hyacinth in adsorbing the lead (Pb) metals. Determination of adsorbed metal content in the charcoal and the activated charcoal was measured using a spectrophotometer spectrodirect. Activated water hyacinth charcoal was prepared by carbonization in a furnace at a temperature of 300 oC in low oxygen levels. Then the carbon was activated by adding ZnCl2 10%, soaked for 24 hours, filtered and placed in the oven at a temperature of 105 0C for 1 hour. The optimum pH was determined by mixing Pb2+ with water hyacinth (eichhornia crassipes) charcoal at various pH of 3-8. The results indicated the optimum pH of charcoal and activated charcoal to adsorb metals was 5 with the percentages of lead absorbed were 90.34% and 98.67%, respectively, while the weight of charcoal varied by 25, 50, 75, 100 and 125 mg, the optimum weight of activated charcoal was 100 mg with lead absorbed by 98.44%. The results showed that the water hyacinth charcoal and activated charcoal performed excellent ability to adsorb lead metal.

The research about the balancing of redox reaction on chemistry subject has been done. This research was conducted on class XII IPA8 SMA Negeri 2 Palu with 28 of the student, in the first semester of the academic year 2014-2015. The research method used is a descriptive qualitative in which data processing use percentages and rating scale. The data is collected by observation sheets, questionnaires, and documentation. Implementation of lesson study on class XII IPA8 SMA Negeri 2 Palu is conducted in three meetings time (open class) with 3 phases; plan, do and see, respectively. Based on the results obtained every meeting by the researcher, the data activity of students is rising by 54.93, 59.86, and 74.30%. Furthermore, at the third meeting, the data obtained is an excellent category which means the student’s activity in the lesson study was increased. These prove that through the lesson study can increase the activity of the learning process of students. In addition, based on the data analysis of the student’s learning outcomes during three meeting times is increased. Average of completeness of student’s learning outcomes of every meeting is 67.85, 85.71, and 100%, respectively. Again, these prove that the student’s learning outcomes by classical can be increased through the lesson study.

This study aimed to identify bioactive compounds of moringa (moringa oleifera) extracts and determine the effective concentration on lowering blood cholesterol levels of mice. The animals used were 15 male mice induced by propylthiouracil and fat food diet. The mice were divided randomly into 5 groups with different treatment groups. The first, the second, and the third treatments were given moringa extracts each with a concentration of 10, 20% and 40%. The fourth treatment group was given food fat diet and propiltiorasil as a positive control, and the fifth treatment was given standard food and distilled water as a negative control. Data were analyzed using a statistical analysis of variance (ANOVA) test followed by Duncan test. The results showed that moringa fruit extract contains alkaloids, saponins, flavonoids, and tannins. Moringa fruit extract can lower blood cholesterol levels of mice with the most effective concentration of 10%.

The most fish species live in lake Lindu is mujair fish with the average number production of 1080 per day. The scales and fins of mujair fish are the biggest waste that is produced from the processing of this fish and they were just thrown away, which can pollute the environment. The aim of this study is to analyze the level of calcium (Ca) and phosphorus (P) on waste of mujair fish (scales and fins) from the lake Lindu as a basic ingredient of a liquid organic fertilizer. Samples of the scales and fins were taken from a seller mujair fish at Touwa street Palu. To analyze the level of calcium (Ca) and phosphorus (P) from the scales and fins was used a Spectrodirect. Based on the results of the analysis, the average of level of calcium (Ca) in the scales and fins was 4.98 mg/L and 33.33 mg/L, while the average of level of phosphorus (P) was 73.33 mg/L and 145.33 mg/L. The average concentration of dry weight of Ca in samples of the scales was 3,32 mg/kg and the fins was 22,22 mg/kg. The average concentration of the dry weight of P in samples of the scales was 48,88 mg/kg and the fins was 96,88 mg/kg. The results of this analysis showed that the highest concentration of calcium (Ca) and phosphorus (P) was in the fins of mujair fish.

Moringa seed (moringa oleifera L.) is a kind foodstuffs that contains calcium. Calcium is a mineral that is needed by our bodies in all ages, for the infants to the elderly. Calcium is useful in the formation and maintenance of bones and teeth. The aim of this study is to determine the concentration calcium (Ca) in moringa seed (moringa oleifera L.) and its utilization as the fabrication of toothpaste. The method used in this study was a laboratory experiment using a flame photometer. The results showed that the concentration of calcium in moringa seeds with three repetitions was 131.67 ± 12.58 mg/100g. The appropriate composition of materials to make toothpaste from moringa seeds including the roughness tests of toothpaste and based on the fondness of panelists was 25:5 (morinanga seed:NaHCO3). Furthermore, the test of freshness, aroma, and colour with comparison of glycerin, mint leaves, betel leaves and food coloring 7.5: 5: 5: 2.

Mango (Mangifera indica L) seeds never to used, so they need efforts to be as food ingredients suchas flour. Gadung mango seed was one type of mango seeds used as flour. This study aims to determinethe nutrient content i.e. carbohydrates, fats, and proteins of Gadung mango seed flour produced throughsulfurization and without sulfurization. Sodiumbisulfite (NaHSO3) with a concentration of 730 ppmwas used for mango seed soak for 4 hours at sulfurization stage. The results showed that the Gadungmango seed flour through sulfurization had levels of 13.89% carbohydrate, 12.94% fat and 8.48%protein, while the mango seed flour without sulfurization had levels of 20% carbohydrate, 14.83% fat,and 4.84% protein. The technique of sulfurization on making mango seed flour can reduce levels ofcarbohydrates and fats as well as maintaining the protein content.