Bonding Chemical Properties

This lab was conducted in order to determine the melting points of five samples: pure urea, pure trans-cinnamic acid, 90% Urea and 10% trans-cinnamic acid, 50% Urea and 50% trans-cinnamic acid, and 10% Urea and 90% trans-cinnamic acid. The melting points of the substances listed above were obtained by placing 1-2mm samples of each substance in a Mel Temp. From the obtained melting points, a binary phase diagram was created.

Abstract: One mixture of two unknown liquid compounds and one mixture of two unknown solid compounds were separated, isolated, purified, and characterized by boiling point. Two liquid unknowns were separated, isolated, and purified via simple distillation. Then, the process of an acid-base extraction and washing were used to separate two unknown compounds into two crude compounds: an organic acid and a neutral organic compound. Each crude compound was purified by recrystallization, resulting in a carboxylic acid (RCO2H) and a pure organic compound (RZ). The resulting mass of the pure carboxylic acid was 1.688g with a percent recovery of 31.80%, the boiling range was 244-245 °C, and its density was 2.0879g/mL. The resulting mass of the pure organic solid was 2.4902g with a percent recovery of 46.91%, the boiling range was 52.0-53.4°C, and its density was 1.5956 g/mL.

Samples of benzophenone, malonic acid, and biphenyl were each tested with water, methyl alcohol, and hexane. Benzophenone was insoluble in water as it is nonpolar while water is highly polar. Benzophenone was soluble in methyl alcohol, dissolving in 15 seconds, because methyl alcohol is intermediately polar as benzophenone is nonpolar. Methyl alcohol is polar but not as much as water. Thus, the nonpolar benzophenone was soluble in methyl alcohol. Benzophenone was partially soluble in hexane because hexane is nonpolar as is benzophenone. Thus, benzophenone was dissolved in hexane. Malonic acid was soluble in water because both malonic acid and water are polar. It took 25 seconds for malonic acid to dissolve in water. Malonic acid was soluble in methyl alcohol because malonic acid is polar and methyl alcohol is intermediately polar, allowing malonic acid to dissolve in the methanol in 15 seconds. Malonic acid was insoluble in hexane because hexane is nonpolar while malonic acid is polar. Biphenyl was insoluble in water as water is highly polar whilst biphenyl is nonpolar. Biphenyl was partially soluble in methanol which is intermediately polar whilst biphenyl is nonpolar, allowing it to dissolve a little. Biphenyl was soluble in hexane because both biphenyl and hexane are nonpolar molecules. Biphenyl dissolved in hexane in 10 seconds.

6. The solubility of the solids were tested using a micro tray, by placing them in water and oil to observe their polarity,

Maleic acid and fumaric acid have different molecular structure. Maleic acid has a lower melting point than Fumaric acid which has a higher melting point. The reason why is because maleic acid has intramolecular forces, being a cis isomer, which causes it to have weak bonds. This causes it to be easily broken when energy is put in. On the other hand, fumaric acid has intermolecular forces, being a trans isomer, which has stronger bonds. This is harder for bonds to break because of how far apart the carboxylic acid groups are. In addition, maleic acid is more soluble than fumaric acid. Maleic acid has hydrogen bonding due to its intermolecular forces. This causes it to be attracted to water and dissolve. While fumaric acid does not have any hydrogen bonding because of its intramolecular forces which makes it harder for fumaric acid to dissolve in water because it fumaric acid is not attracted to

The purpose of this experiment was to classify unknown solids based on their type of chemical bonds by investigating their properties. By using data, Unknown 1 was classified as a metallic. This was because it appeared a shiny copper color, had a very high conductivity as a solid, had a high melting point, and was malleable. Unknown 2 was classified as a nonpolar covalent bond. This was because it had no conductivity as a solid and low conductivity in water.

Ionic and Covalent Bonding Ionic and covalent bonding is involved when the atoms of an element chemically combine to make their outer shells full and to make the atoms stable. The first type of bonding you can get is ionic bonding. Electrons are transferred from one atom to another to try and create full outer shells, this gain and loss of electrons on the atoms results in positive and negative ions. In these compounds you get electrostatic force, this is the force/attraction that occurs between the positive and negative ions that hold the compound together.

Objective: The objective of this experiment is to use acid-base extraction techniques to separate a mixture of organic compounds based on acidity and/or basicity. After the three compounds are separated we will recover them into their salt forms and then purify them by recrystallization and identify them by their melting points.

These two are isoelectronic so the London force should be the same. This is manifested in similar boiling temperatures.

A small capillary was used and pressed into the three samples and placed in a melting point apparatus. The melting point was set to start at 75°C and increase at a rate of 2°C per minute. The point at which melting started and finished was recorded. The melting ranges were then compared to that of the possible compounds and a preliminary determination of compound identity was made.

The physical properties, such as melting point and color, and chemical properties, such as reactivity with a base or acid, can help determine the type of attractive force or chemical bond a solid has. In this lab, four types of chemical bonds were taken into consideration: metallic, ionic, and polar and nonpolar covalent. Metallic bonding is usually found in metals like zinc and is the force of attraction between mobile valence electrons and metal cations while ionic bonding is between two oppositely charged ions. Covalent bonding is another type of chemical bond and occurs between two or more atoms by a sharing of electrons. These bonds can be identified as either polar or nonpolar. While nonpolar bonds have an equal sharing of electron and

For example the results of melting point and solubility experiments if test tube B came as test tube B has higher melting point and more solubility in water than test tube A, therefore, test tube B is a Maleic acid and test tube A is Furamic acid. Based on the structure of each acid, maleic has a cis configuration of carboxylic group in the same side which makes it polar and the hydrogen bonds are weak which take less thermal energy to break them apart therefore more soluble in water. Whereas in Furmaic (test tube A) structure has a Trans (opposite) carboxylic group which make it less soluble and higher melting point than Maleic

properties has been investigated as well as acid stability. The new gels show that control over

The purpose of this lab was to study colligative properties. These properties are properties that are affected when a solute is added to a solvent. Thus, the amount is important, not the actual type of substance, for the colligative properties. A couple types of this property are the freezing point and boiling point of a substance. (1)

As mentioned in the discussion, olive oil, vegetable oil, crisco, and lard were soluble in nonpolar solvents and insoluble in polar solvents. This is due to the chemical composition of polar and nonpolar substances which results from the molecular shape as well as properties of dissolving solutes in solution. Polar substances are hydrophilic and contain polar Van Der Waals interactions (intermolecular forces) such as dipole-dipole forces, ion-dipole forces, and hydrogen bonding. Nonpolar substances are hydrophobic and contain non-polar Van Der Waals interactions. ‘Like dissolve like’ is the reason only polar solutes dissolve in polar solvents and why nonpolar solutes dissolve in nonpolar solvents. Molecules with similar polarity have similar intermolecular forces and therefore, can interact with each, or in this case dissolve9. Additionally, the solubility of a compound is determined by the length of the hydrocarbon chain. Long hydrocarbon chains such as the one found in oleic acid makes a compound more insoluble10. Therefore, since the lipids used in this experiment were hydrophobic substances and each lipid has long hydrocarbon chains, the results were consistent with the scientific literature and principles.