Identification of a Liquid
Objective
This experiment was performed out to determine the identity of an unknown liquid sample by investigating its solubility in water, hexane and ethyl alcohol. Also, its density and boiling point were obtained and compared to the theoretical values.
Theory
Chemical substances can be identified through investigation of their chemical and physical properties and then comparing the experimental values to the standard values. Physical properties do not change the chemical composition of the substance. Physical properties include; density, boiling point, and solubility, etc. The density of a substance is the ratio of the mass of the substance to its volume. Density (ρ) = mass (M) / volume (V). The boiling point of a substance is the temperature at which the liquid form of the substance starts to change to its vapor form. Solubility is defined the degree at which a substance (solute) dissolves in another substance (solvent). Solubility is affected by factors such as temperature, …show more content…
Equal amounts of water, hexane, and ethyl alcohol were added to the test tubes and mixed thoroughly. The solubility of the sample was observed and noted. This procedure was repeated using Naphthalene and paraffin as the solutes.
Density determination
Mass of a beaker was measured. Then, a volume of 10mL of the unknown substance was placed into the beaker and the mass of the beaker and the sample measured. Using the obtained mass of the unknown liquid, its density was calculated.
Boiling point determination
One mL of the unknown liquid was placed in a test tube and then placed in hot water bath. Using a thermometer the temperature at which the liquid started boiling was noted.
Results
Table 1. Solubility of the liquid
Substance Solubility in Water Solubility in Hexane Solubility in Ethyl alcohol
Naphthalene i s ss
Paraffin oil i s i
Unknown liquid i s
Objective
This experiment was performed out to determine the identity of an unknown liquid sample by investigating its solubility in water, hexane and ethyl alcohol. Also, its density and boiling point were obtained and compared to the theoretical values.
Theory
Chemical substances can be identified through investigation of their chemical and physical properties and then comparing the experimental values to the standard values. Physical properties do not change the chemical composition of the substance. Physical properties include; density, boiling point, and solubility, etc. The density of a substance is the ratio of the mass of the substance to its volume. Density (ρ) = mass (M) / volume (V). The boiling point of a substance is the temperature at which the liquid form of the substance starts to change to its vapor form. Solubility is defined the degree at which a substance (solute) dissolves in another substance (solvent). Solubility is affected by factors such as temperature, …show more content…
Equal amounts of water, hexane, and ethyl alcohol were added to the test tubes and mixed thoroughly. The solubility of the sample was observed and noted. This procedure was repeated using Naphthalene and paraffin as the solutes.
Density determination
Mass of a beaker was measured. Then, a volume of 10mL of the unknown substance was placed into the beaker and the mass of the beaker and the sample measured. Using the obtained mass of the unknown liquid, its density was calculated.
Boiling point determination
One mL of the unknown liquid was placed in a test tube and then placed in hot water bath. Using a thermometer the temperature at which the liquid started boiling was noted.
Results
Table 1. Solubility of the liquid
Substance Solubility in Water Solubility in Hexane Solubility in Ethyl alcohol
Naphthalene i s ss
Paraffin oil i s i
Unknown liquid i s