I believe its a covalent bond?
Answer:
Dissolve the impure solid in a minimal amount of boiling solvent, cool the solution to form crystals, vacuum filter the solution to collect the pure crystals.
Explanation:
Recrystallization is a process when a solid with impurities is purified. To do this a solvent of the compound we want must be used. We need to use only the quantity necessary to dissolve the compound of interest, otherwise, the solvent will dissolve the impurities or it will interfere in the crystallization.
For most of the solids, the solubility increases with the increase of the temperature, so to speed up the process, heat must be added at the system, or the solvent must be boiling. Then, the solution will be cooled to form the crystals of the compound purified, and then it must be filtered in a vacuum because the crystals can slow down the filtration.
<span>Magnesium is a strong anode than calcium. So, Mg will be oxidized into Mg2+. So instead of having Ca being the reducing agent, Mg will takes its place. That's how the "Blocking" occur.
</span><span>Without Ca2+, no neurotransmitter was released because the exocytosis of the synaptic vesicles is dependent upon Ca2+.
</span>So, when magnesium is added to the extracellular fluid it blocks the calcium channels and inhibits the release of <span>neurotransmitter.</span>
Answer:
Acid rain this results when gaseous emissions of sulphur oxide, nitrogen oxide etc come in contact with water vapour and sunlight and are chemically converted to strong acidic compounds such as sulphuric acid, nitric acid etc, and are carried to the earth by rain drops, snow flakes, flog or dew.
