INFORMATIVE SPEECH Does Like Dissolve Like? Introduction I. Most of you have probably been to the dermatologist at some point in your life. a. Your dermatologist most likely recommended an oil free cleanser. b. Oil causes acne, right? c. Recently, some groups have questioned this universal. II. Audience Connection/Value Statement- We can all recall the solubility rule “like dissolves like” from chemistry. Those who question the oil-free regimen have taken this principal
using this form of paper chromatography to separate mixtures, as we have grasped an understanding as to how this form of chromatography allows for us to identify the polarity of each constituent substance. Thus, during the examination of mixtures, we will be able to identify each component based on factors such as its Rfvalue and polarity. Potential errors in this lab could have occurred in many facets. One of our procedural errors involve our failure to mark the distance traveled by the solvent in
amount of organic acids in the food sample. This all acids (tartaric, oxalic acid, citric acid, sulfuric acid, lactic acid and acetic acid) The acidity can be determined by using titration method. Titration is a laboratory method of quantitative chemical analysis that uis used to determine the unknown concentration of a known reactant. Because volume measurements play
Many of the substances that exist in the universe are a result of chemical reactions involving bonding. Ionic, Covalent and Hydrogen bonding are essential to the formation of the world that we know today. The first type of bond involves the transfer of electrons from one atom to the next. This type of bond is known as Ionic bond and occurs between a metal and a nonmetal atom. These bonds are typically stronger than covalent bonds and involve atoms that have a large difference in their electronegativity
Chemical bonds are really important to todays scientist. But, what are the three most important chemical bonds? A chemical bond is an atomic attraction between molecules by sharing electrons between two atoms or a transmission of electrons. The three major chemical bonds are the following ionic, covalent, and hydrogen bonds. An ionic bond is a transfer of valence electrons between two atoms. An example of this bond would be Sodium Chloride or (NaCl). Ionic bonds are high polarity, no definite shape
The chemiluminescence part of the experiment, we had to make four solutions labeled as ‘stock solution A, solution A, stock solution B, and solution B’. For the ‘stock solution A’ we put the luminol product, (0.242 g) in a 25 mL Erlenmeyer flask and dissolve it with 2 mL of 3M NaOH. Then we took 1 mL of the ‘stock solution A’ and diluted in 9 mL of water using a 50 mL beaker. Solution A. For the ‘stock solution B’ we mixed 4 mL of potassium ferricyanide solution and 4 mL of hydrogen peroxide solution
heteroatom substituent will produce a carboxylic derivative, which include amides, anhydrides, esters, and nitriles. The polarity of the acyl carbon atom is produced by the substituent and the electronegativity of the C-O double bond. The additional electrophilicity from the polarity increased the acyl carbon’s
A second type of packing material is called pellicular, consists of small beads coated with layer of a porous material such as silica gel, alumina or ion exchange resin. 6. Detector This detector is used for measurement of specific physical and chemical properties of the column effluent. The most common detector used in pharmaceutical analysis is UV, which allows monitoring and continuous measurement of the UV absorbance at a selected wavelength. Appearance of the analyte in the detector flow-cell
Chapter 2 Fundamental Building Blocks: Chemistry, Water, and pH 1. Cells that make up complex living things do what they do because of a chemical reaction 2. Repulsion & bonding, latching on & re-forming, depositing & breaking down what makes people plants and birds function at this level is chemistry 2.1 Chemistry’s Building Block: The Atom 1. Matter could defined as anything that takes up space and has a mass 2. Mass it’s a measure of matter in any given object 3. Atom are composed of tiny
do not conduct electricity when in a solid state, but only when dissolved in water or melted. Ionic compounds also tend to be solid at standard pressure and temperature. Also, because of the difference in electronegativity, they tend to have high polarity too. The melting point of magnesium chloride is 714oC, and its boiling point is 1 412oC. These melting and boiling points are quite high – since ionic compounds use up a great amount of energy to break their bonds. Magnesium chloride is also soluble
In this research paper, I am going to investigate on how the concentration of Sodium Chloride (NaCl) solution affects the volume of the gases (Oxygen gas and Chlorine gas) at the anode during the electrolysis of sodium chloride solution. In my previous chemistry classes, I have learnt that concentration affects the majority of the gas produced at the anode. This made me wonder, how does the ratio of oxygen gas to chlorine gas produced at the anode vary at the electrodes. This made me formulate the
Chemical Bonding S00143856 Emma Butler 22/10/14 Chemical Bonding “We define the chemical bond as an interaction between atoms associated with a collectivization of the valence electronic orbitals” (Bersuker 2010). This meaning that we look at a chemical bond and categorise it according to where the valence electrons are found in the molecules. As the valence electrons determine the chemical properties of the molecule, based on the properties of the molecule we can determine the type of bonding
A boiling point of a substance is dependent on the temperature at which the substance can change its matter, such as liquid to gas. The molecules present in liquid are tightly compressed together, though they are still moving and colliding. If the liquid is heated, there is a rise in temperature which generates vibrations throughout the liquid, resulting in more collisions between molecules (Helmenstine, 2017). Once the collisions between the molecules become quite intense and rapid, boiling starts
Objective #1 Compare the differences between ionic and covalent bonding and how molecules are formed by either ionic or covalent bonds. IONIC BONDING: Ionic Bonding is the complete transferring of valence electrons between two atoms. This type of chemical bonding results in two oppositely charged ions, a cation and an anion In ionic bonding the electrostatic attraction between the charged ions holds the compound together. Example: Bonding of Sodium and chlorine. 1s2 2s2 2p6 3s1 Fig
In the periodic table lithium’s atomic number is 3. The atomic number describes the number of protons in the nucleus and the number of electrons in the atom when it is not ionized. (An ion is an atom where the amount of protons and electrons is not equal.) Lithium has 3 protons; therefore it must have 3 electrons when it is not ionized. The protons and neutrons together form the nucleus. Lithium has 3 protons and usually 4 neutrons since its atomic weight is 6.9 according to the periodic table
mobile phase. A monster placed on a stationary phase, i.e., a solid or a liquid, and the mobile phase, a gas or a liquid, is allowed by modifying the system. The components of the sample will be separated on the basis of their ranging physical and chemical properties, imparting different affinities for the two phases. Thin layer chromatography (TLC) was the first chromatographic method for assessing phospholipids, and is commonly used today.
2.3.2.2 Chemical Interesterification Chemical interesterification is the process to redistribute the component of fatty acid and glycerol ions to form new gylcerolester with the presence of sodium methoxide as a catalyst. Chemical interesterification is also known as directed interesterification since this reaction is directed to produce a particular type of glyceride (O’Brien, 2009). This process is conducted at mild temperature with a range between 20°C to 100°C. O’Brien (2009) states that only
product depending on whether the overall reaction is exothermic or endothermic so adding heat would decrease K. 55. limiting reagent, stoichiometry Upon determining which one of the given reactants is the limiting reagent, simply use the balanced chemical equation, upon ascertaining that it is in fact balanced to find the desired number of moles of desired product. Would most simple to solve out each number of moles of each given reactant and then take the smallest result because that’s the limiting
Physically, the unknown compound was composed of white, grainy, crystal-like structures. The unknown was also odorless. From these observations, various physical and chemical testing was performed to determine properties of the unidentified compound. A series of solubility tests were performed, as shown in Table 2, and revealed that the unknown compound was soluble in water, but not in Acetone or Toluene. Because the compound dissolved in water, it is known that the compound is either polar or
Introduction The term chromatography actually means colour writing, and signifies a technique by which the substance to be examined is placed in a vertical glass tube containing an adsorbent, the different segments of the substance traveling through the adsorbent at distinctive rates of velocity, according to their degree of attraction to it, and producing bands of colour at different levels of the adsorption column. The substances least absorbed emerge earliest; those more strongly absorbed emerge