Lab 2 - which is the process by which fine particles clump...

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Andrea Kam Section 4 1. The class of material that must be added to a eutectic mixture to prepare it as a powder is an absorbent, such as talc. 2. According the U.S. Pharmacopeia, the chemical composition of calamine is zinc oxide (ZnO) with a small amount of ferric oxide (Fe 2 O 3 ) 3. The purpose of calcium hydroxide topical solution in calamine lotion is to act as a topical astringent, which firms up the skin by coagulate the skin proteins, shrink the pores, and restore the protective layer and thus reducing irritation. In addition, the calcium hydroxide is very basic so it neutralizes the acidity of poison ivy oil, thus reducing irritation. 4. It is important not to shake calcium hydroxide topical solution before pouring it because calcium hydroxide is a flocculent, which is a chemical that promotes flocculation which causes suspended particles in liquids to undergo flocculation,
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Unformatted text preview: which is the process by which fine particles clump together into floc. The floc of calcium hydroxide could settle to the bottom of the liquid. The calcium hydroxide solution is saturated and if shaken the solid will be on the bottom. 5. Preparing methylcellulose solution with cold water is difficult because it forms a sticky film around the powder and inside will remain dry. Hence, in order to prepare a methylcellulose solution you need to mix the powder with hot water. Once, the methyl cellulose particles are well dispersed in water and and cool down this dispersion while stirring, which will cause dissolution of the methylcellulose particles. 6. The calcium hydroxide is responsible for the pH of calamine lotion....
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