Elements bond in fixed ratios and so can be represented by a chemical formula. For example, sodium chloride has the same number of sodium ions and chloride ions, so its formula is NaCl ...
Sodium polyacrylate molecules are very long and curly. The sodium parts, represented by the green circles and chemical symbol Na, have a positive charge and dissolve in water. The long portion of the ...
A seed crystal can be dropped into a saturated solution of sodium acetate. The solution will suddenly crystallize and turn to solid. Alternately, the solution may be slowly poured out onto a seed ...
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