... a characteristic of crystallization hygroscopic, soluble in water, and water solution shows neutral. Soluble in glycerin, not soluble in alcohol. When exposed to ... compound (Na2SO4 · 7 H2O) is white trapezius crystal, when heated up to 24.4 °C , it will turned into anhydrous ... compound. When sodium reacted with carbon, it will be reduced to zinc sulfide colloid. It could ...