The solubility of ionic compounds in aqueous solutions is wide and varied. Some compounds are highly soluble (e.g. NaCl), some compounds are moderately soluble (e.g. SnI2) and some compounds are highly insoluble (e.g., AgCl). Determining which compounds are soluble and not soluble in a water medium is not a simple task.
For us in the Northern Hemisphere, the December solstice marks the longest night and shortest day of the year. Meanwhile, on the day of the December solstice, the Southern Hemisphere has its longest day and shortest night. This special day is coming up on Tuesday, December 22 at 4:48 UTC (December 21 at 10:48 p.m. CST). No matter where you live on Earthâs globe, a solstice is your signal to celebrate.
Each time the moon moves into line with the earth and the sun a new month begins and this is called 'Chu Yi' or 'Shuo Ri' (the first day of a lunar month). The longest day of a year or Summer Solstice falls on the 21st or 22nd of June, and the shortest day is the Winter Solstice on either December 21, 22, or 23. Using these two annual events the year was divided into in 24 equal parts, each forming the 24 solar terms.