3) Write equations to indicate what you consider to have happened in each case in which there was precipitate formed. Use ions to represent the species in the reacting solutions, but for those products that were precipitates write a formula for the compound. Place (aq) after those species in solution and (s) after the precipitates. Be sure to write the equations so that both atoms and charge are conserved. For example: Ag+(aq) + NO3-(aq) + Na+(aq) + Cl-(aq) ( AgCl(s) + Na+(aq) + NO3-(aq) 4) Rewrite the equations, leaving out the ions not involved in the reaction (spectators).
An aqueous solution of ammonium sulfate is allowed to react with an aqueous solution of lead(II) nitrate. Identify the solid in the balanced equation. A) (NH4 )2 SO4 B) Pb(NO3 )2 C) PbSO4 D) NH4 NO3 E) There is no solid formed when the two solutions are mixed. ____ 11. An aqueous solution of sodium carbonate is reacted with an aqueous solution of calcium chloride.
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.
Then the leach solution is purified by separating the waste from the desired materials. The final step is precipitating the metal, or one of its pure compounds from the leach solution by chemical or electrolytic means. This lab is focused on determining whether an unknown sample is chromite or not. Chromite contains magnesium, iron, and chromium, and it must be determined if the sample contains each of these metals. In order to do that, each metal must be extracted separately.
This was so that the mussel samples would not go bad due to heat or harsh solvents. They were extracted with a mild solvent, and then concentrated by evaporation. The team found that the vapor was not toxic, but the residue after was. Other extractions were done to see how the residue separated when added with other mixtures of nonpolar solvents. In the toxic mussels, the visible light absorption spectrum revealed a pattern that was characteristic of phytoplankton pigments.
Solubility and Conductivity Introduction Solubility by definition means “the quality or property of being soluble; relative capability of being dissolved” and in chemistry this tells us whether or not a substance is dissolvable, but in the medical field it can mean you have a homeostatic imbalance (Webster, 2010). They use “a screening test for sickle cell hemoglobin (Hb S), which is reduced by dithionite and is insoluble in concentrated inorganic buffer; addition of blood showing Hb S to buffer and dithionite causes opacity of the solution” (Solubility, 2012). This is just one of many uses of solubility in the medical field. Conductivity by dictionary definition is “Physics. The property or power of conducting heat, electricity, or sound” and is used as such in chemistry (Dictionary, 2014).
Then measure the distance of each pigment starting at the bottom of the pigment origin to the bottom of the separated pigment band. In Exercise 4B: Photosynthesis/ The Light Reaction, chloroplasts are extracted from spinach leaves and incubated with DPIP in the presence of light. The spectrophotometer should be warmed up and set the wavelength to 605 nm. An incubation area should be set up, that includes a light, water flask, and test tube rack. We were provided with two beakers, one containing a solution of boiled chloroplasts and
Strong electrolytes produce large numbers of ions, which results in high conductivity values. Weak electrolytes result in low conductivity, and non-electrolytes should result in no conductivity. In this experiment, you will observe several factors that determine whether or not a solution conducts, and if so, the relative magnitude of the conductivity. Thus, this simple experiment allows you to learn a great deal about different compounds and their resulting solutions. In each part of the experiment, you will be observing a different property of electrolytes.
EXPERIMENT 6 Title Kinetics of Chemical Reaction – Iodination of Cyclohexanone Aim To determine the value of the rate constant, k and order of reaction, a, b and c, and also to suggest a mechanism which agrees with the rate equation that has been obtained. Background Theory The basis of the theory of absorbance is as follows: Io ―――――→ sample ―――――→I if Io = I, no absorbance occur Io > I, the sample absorbs certain amount of light wave Io < I, the sample emits certain amount of light of certain wave length. THE HALOGENATION (IODINATION) OF KETONES (CYCLOHEXANONE) This experiment examined the rate of iodination of cyclohexanone in an aqueous medium. To increase the amount of iodine in the solution, iodine is converted to a more soluble complex ion, I3- by the addition of excess iodide ion: I2 + I- →I3- One of the characteristic reactions of ketones is the substitution of a halogen for one of the hydrogen is adjacent to the ketone group. The net reaction is: This reaction has been studied extensively and occurs for a wide variety of ketones.
In the field of medical imaging science Molecular imaging has emerged as one of the most promising fields. It comprises of a diverse number of imaging modalities including Optical imaging (OI) and nuclear imaging techniques such as Positron emission tomography (PET). Both of these techniques are characterised by various properties that make them desirable in imaging i.e. PET has an excellent sensitivity and quantification ability whilst OI is relatively low cost and widely available1. An optimised imaging modality would result from a combination of these properties.