1. “what forms of energy conversions occur during the process of photosynthesis? (How does energy transform?)
2. What is missing from the food web but is essential to maintain equilibrium?
A. Soil
B.water
C. Decomposers
D. Oxygen
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.
C and D
surface water is evaporated by the sun and concentrated the ocean salt and oceans are diluted when rivers flow into them
Answer:
physical
Explanation:
no chemical reaction occurs
