Properties of Ionic and Covalent Substances Lab Report Introduction The purpose of this lab was to determine which of the following substances: wax, sugar, and salt, are an ionic compound and which are a covalent compound. In order to accurately digest the experiments results, definitions of each relating factor were researched, leading to the following information: ionic compounds are positive and negatively charged ions that experience attraction to each other and pull together in a cluster of ionic bonds; they are the strongest compound, are separated in high temperatures, and can be separated by polar water molecules. A covalent compound is formed when two or more nonmetal atoms share valence electrons; covalent compounds are also categorized into two sections: polar covalent and nonpolar covalent. Furthermore, polar covalent compounds dissolve in water, while nonpolar covalent compounds do not. Dissolving is the process in which a solvent and a solute interact with each other and form a solution.
When an aromatic compound such as phenol undergoes nitration, it does so through an Electrophilic Aromatic Substitution (EAS). Undergoing this reaction requires two steps. The first step is the addition of the electrophile, which in this lab was the Nitronium ion formed by the dilute nitric acid solution. This is the rate determining step for this reaction, as during this step aromaticity is lost and the arenium ion is formed. The position of the electrophile to be added is determined by how well the arenium ion can be stabilized once the initial addition occurs.
Diffusion is the force that causes molecules of a substance to diffuse from of high concentration to regions of low concentration. If the concentration of potassium ions is unequal across the cell membrane, potassium ions will diffuse through the selectively permeable membrane until they are equally concentrated on both sides. Diffusion results from the concentration gradient generated by the sodium-potassium pump. This mechanism, powered by ATP, pumps three sodium ions out of the cell for every two potassium ions pumped into the cell, causing a build up of potassium ions inside the cell. Potassium ions diffuse out the cell due to the concentration gradient, creating a potential difference across the membrane.
Basically, the bottom layer is the aqueous layer while the upper layer is the organic compound. However, this situation may be vice versa due to the relative densities of the two solutions. The extraction process is used to repeat in several times in order to ensure all of the organic compounds are fully drained out. Granular sodium sulfate will act as drying agent to remove the last traces of water from organic
The effect of pH on the speed of enzyme interaction with substrate chemicals Hypothesis: About pH: If the pH level is less than 5, then the speed of the enzyme reaction will be slower. About temperature: If the temperature stays the same, then the speed of the enzyme reaction will not be completely affected. Background information: The function of enzymes is to speed up the biochemical reaction by lowering the activation energy, they do this by colliding with the substrate. All enzymes are under the class of protein biomolecule. Amino acids are the basic units that are combined to make up an enzyme.
The purpose of this lab is to observe the reaction between hydrochloric acid and magnesium metal. When the substances are reacted over water, the products produced are a salt in aqueous solution and a gas. While the salt remains in the water as part of a solution, the gas produced will float to the top. Though water vapor pressure will affect the pressure of the gas in the eudiometer, it is possible to apply Dalton’s law of partial pursues to find the dry pressure of the gas. When the dry pressure is determined, the volume of the gas at STP can then be determined and what the experimental volume of one mole of the gas would be at STP.
Solubility matters since organic compounds tend to not be soluble in aqueous solvents, but ionic salts do easily dissolve in water. And acidity matters since we can adjust the base strength to only react with one component of Excedrin at a time, allowing for the components to be isolated. By adding a 1M solution of a basic salt, like K2HPO4 or KOH, to organic compounds, we could convert the organic components of Excedrin into ionic salt that will dissolve in aqueous solvents. Next, by adding a strong acid, like HCl, the Excedrin component is protonated causing a decrease in solubility leading to the component precipitating out of the solution and crystallizing. Acid-base extraction offers a method to separate the active components of Excedrin based on acidity and what bases they will react with.
Lab Report -- Relationship on Enzyme activity and substrate concentration Research Question: Is the more concentrated the substrate of hydrogen peroxide is, the shorter the time taken for the paper disc to rise from the bottom of the beaker? Aim: The opposite of hull hypothesis Background Information: This experiment aimed to investigate on the relationship of the substrate concentration and enzyme activity. Enzymes are proteins produced by a cell that acts as catalysts to increase the rate of a specific chemical reaction without changing the reaction itself. Under some conditions, substrate will bind to the active site of an enzyme and form an enzyme-substrate complex. The enzyme would fasten the chemical reaction and the substrate will
Title: Diffusion & Osmosis Purpose: The purpose of this experiment was to test the tonicity of the different solutions. Background: Diffusion and osmosis are both processes that occur within the plasma membrane. Diffusion is the process by which molecules intermingle as a result of kinetic energy. Osmosis is the movement of water across a semi-permeable membrane. Tonicity is also related to osmosis.
Generating and maintaining RMP The diffusion potentials of different ions establish the resting membrane potential. The concentration difference between the permanent ions like Na+ and K+ ions maintains the RMP through the Na+-K+ Pump. b. Generation and propagation of action potential Various ions on wither side of the cell membrane alter the membrane potential over time. Once this reaches the threshold potential, there is depolarization.
A Gly-chloride ion boundary is formed since glycine moves slower than chloride ion. However, glycine still runs slightly faster than other proteins. As a result, the glycine keeps pushing the protein towards the chloride ion. In other words, the proteins are trapped between glycine and chloride ion. The proteins form a very tight band inside the stacking gel.
The purpose of this experiment was to see which solute, Splenda, granulated sugar, or salt, would dissolve the fastest in distilled water. Solutes can only dissolve in solvents when they are polar. A polar bond is a covalent bond that has two atoms where the electrons forming the bond are unequally distributed (About Education.com). This causes it have a dipole or separation of electrical charges moment making it polar. For example, in a water molecule the electrons are not shared equally because the oxygen has more of a charge than the hydrogen bonds making the hydrogens pull towards the oxygen.
The objective of the lab was to understand the Law of Conservation of Mass. The Law of Conservation of Mass states that matter can be changed from one form into another, mixtures can be separated or made, and pure substances can be decomposed, but the total amount of mass remains constant. For example, from our experiment in the lab, we observed mass of the mixture of aqueous Sodium Sulfide and aqueous Zinc chloride turned white color. After the filtration, and all the water was evaporated, we measured the mass very close to what we had started at the beginning. The error in mass occurred because of the remained residue (solute) in the beaker.