This is false. They were both chemists and they made many discoveries such as realizing that charcoal and diamond are different forms of the same element and proposing an atomic theory, but they never tried to turn diamonds to gold.
Answer:
The correct answer is:
<em>(1) It is important that the sample is dissolved in just enough hot solvent. </em>
Explanation:
The process of recrystallization is important to eliminate the impurities and to obtain better crystals of the solid. The solvent used to perform the recrystallization must have a high dissolution power of the substance to be recrystallized and a low dissolution power of the impurities. This is in order to eliminate most impurities. Furthermore, <em>It is important that the sample is dissolved in just enough hot solvent </em>because this should be easy to remove after the recrystallization and the crystal should form easily when the solution cools. Also, it is better to add the hot solvent to solubilize the crystals and keep the impurities insoluble, instead of adding the cold solvent and heating the solution. Additionally, the process of cooling the solution must be done slowly to obtain large and fewer crystals. A fast ice-cooling will form smaller crystals.
Answer:
Explanation:
193.02 times 9.55 it's going to be 1843.341
9.55= 191.20 milli
Answer: 175.35g
Explanation: A 3 M solution has 3 moles of solute per litre.
The mass of one mole of NaCl equals the MW of NaCl MW = 35.45 + 23 =58.45 g/mol
The mass of 3 moles is 58.45 g/mol ×3 mol=175.35 g NaCl or 200 g rounded to one sigfig.
Answer:
20.25 W
Explanation:
Applying,
P = I²R.................... Equation 1
Where P = Power, I = current drawn by the test light, R = Resistance of the test light
From the question,
Given: I = 1.5 A, R = 9.00 Ω
Substitute these values into equation 1
P = (1.5²)(9)
P = 2.25×9
P = 20.25 W