Identification of Common Chemicals - 275 Words

Identification of Common Chemicals (Coursework Sample) Content: Name Professor Course Date Identification of Common Chemicals 1. What is the first step in identifying a chemical? Evaluation of the physical characteristics is the first step in identifying a chemical. The physical state of the chemical can be solid, liquid or gas. The colour of the chemical can also be noted in identification of the substance. The shape of the chemical in case of a solid can help identify the compound. Reacting the chemical with acid and bases can help identify its composition. 2. How does a solid substance dissolved in water? Water-soluble substances dissolve by losing their atoms to the negative and positive poles in water. Water molecule contains positively charged hydrogen and negatively charger hydroxyl ions. The attraction by these ions pulls apart the solid and dissolves it into the water. A solid such as sodium chloride dissolves by losing its sodium ions to hydroxyl ions and chloride ions to the hydrogen ion to form a solution with sodium hydroxide and hydrochloric acid. 3. How is flame test performed? Frame test works by exciting the ions in the substance causing emission of a visible light characteristic of the element. A frame test is conducted using a wire loop dipped in hydrochloric acid then distilled water to clean the wire. The wire is then dipped in the substance to be tested and the colour change noted. A chart can be used to easily identify the chemical being tested. 4. How is a litmus paper used in identifying chemicals? Litmus paper works through elimination process. The...