The cooling curve was determined by recording the temperature at regular time intervals (every fifteen seconds) as the cyclohexane cooled, until the temperature became constant. The cyclohexane was stirred continuously. The FP tube was then removed from the ice and the cyclohexane melted. The cooling of the cyclohexane was then repeated twice and the mean of the three values was taken as the freezing point. ~0.1g of benzoic acid was accurately weighed and added to the cyclohexane and stirred vigorously until it had dissolved.
Then, water was added dropwise during the mixing process. The above solution converts of colorless to yellow suspension solution which produced TiO2 nanopowder by drying process at 85°C in anstove for 15 hours. Finally, TiO2 nanopowder obtained were treated in furnace at different temperatures (400°C-800°C) for 2 hours. The initial heating rate was maintained at 5 °C/min. 2.3.
6s2 6p6. 7s2 6. Outline the chemical properties (including its position in the periodic table) Plutonium is placed 94th on the periodic table, which is equivalent to its atomic number. It is located in the Actinide metals section and also the F-block. Chemical Properties: Reaction with air: - When plutonium is exposed to air it begins to oxidise, it forms a yellowish-brown outer coat and begins to tarnish.
In the round-bottom flask (100 mL), we placed p-aminobenzoic acid (1.2 g) and ethanol (12 mL). We swirled the mixture until the solid dissolved completely. We used Pasteur pipet to add concentrated sulfuric acid (1.0 mL) to the flask. We added boiling stone and assembled the reflux. Then, we did reflux for 75 minutes.
The purpose of this experiment was to perform a Wittig reaction using two different methods: In method I, 250 mg aldehyde was mixed with 785 mg phosphonium salt in 5 M NaOH solvent. This mixture was stirred for thirty minutes and filter by vacuum filtration for the product. In method 2, 250 mg of aldehyde, 785 mg, benzyltriphenylphosphonium chloride, and 380 mg potassium phosphate tribasic were homogenize with a pestle and mortar. Vacuum filtration was also used in this method to attain the product. The products in both methods were used for recrystallization and TLC.
This beaker was heated in a hot water bath until the solid dissolved in the solution and was cooled in an ice water bath for 15 minutes. Crystals were gathered via vacuum filtration and the stir bar was removed. The mass of the final product was 0.52g and 57.33 % recovery, with a melting point of 166.5-170.6
It has a melting point of 1585K (which is the same as 1312°C 2394°F), heat of fusion of 10,05 kJ/mol, and boiling point of 3546 K( 3273 °C, 5923 °F). Gadolinium has an electron configuration of [Xe]4f 75d16s2; and vapour pressure of7.39 Pa at temperatures of 2000 K.
Graphite boats are required and temperatures of between 2500° F and 2750° F are used. All small parts are packed in alundum (Al 2 O 3 ) grain. b) Combination Vacuum Sintering: Pre-sintering is done under inert gas or in vaccum at low temperatures until the paraffin has evolved; the gas is then pumped out and the temperature is continuously increased to the final temperature. Vacuum furnaces
The Atomic number of the element is 64, 157.25 g.mol -1 is the atomic mass of this element. The melting point of 1313 °C and the boiling point is 3266 °C. The density per cubic meter is 7.8 grams. The number of isotopes in the element Gadolinium is 13. The element in its natural form is a shiny, ductile, malleable, soft and silver element.
was added to reaction mixture and heating was continued for 4-6 hrs. The reaction was monitored by TLC after 3hrs. Then the reaction mixture was cooled and poured over crushed ice and the product separated out was filtered, washed with water, dried and recrystallized from alcohol. 5-Methyl-1-phenyl-1H-tetrazole (1). White crystals; yield 87 %; mp.
I organized four different tests; pH paper, alkalinity tests, the number of rocks neutralizing acid, and the number of rocks that don’t neutralize acid. The average for pH paper was seven. The pH is the numeric scale used to specify the acidity or alkalinity of an aqueous solution. The pH scale measures acidity and alkalinity. the pH scale goes from zero, which is an acid reading, to fourteen, which is an alkaline reading.
The silver ion TLC was prepared through the following procedure: Silver nitrate was dissolved in 10 ml of distilled water. This aqueous solution of silver nitrate was absolutely mixed with 9 g of silica gel (10 ~ 40 μm particles). Then, a 10 × 5 cm TLC plate was coated with the above slurry and activated for 1 h at 90 °C before use. They were immediately transferred into a desiccator in dark for storage after cooling. 32 100 μL of afore-prepared sample solution and the mixed reference standard were diluted 100 times with ethyl acetate.