TAILIEUCHUNG - Ebook Chemistry experiments: Part 2

(BQ) Part 2 book "Chemistry experiments" has contents: Microscale percent composition, levels of sugar, thin layer chromatography, the rate of rusting, chloride levels, heat energy, chemical moles, finding molar mass, endothermic and exothermic reactions, solutions and spectrophotometry. | 11. Solutions and Spectrophotometry Topic A spectrophotometer can be used to analyze the transmission of light through different solutions. Introduction Solutions are types of homogenous mixtures in which one substance, the solute, is dissolved in a solvent. Solutions can be described as concentrated, where there is a large amount of solute dissolved in a solvent, or dilute, where there is a small amount of solute. However, these descriptions are qualitative and are generally not very precise. Solutions can also be described quantitatively by using molarity (M), the number of moles (mol) of solute per liter of solution. A solution with a high molarity is more concentrated than one with a low molarity. Many chemical solutions are transparent, and the molarity cannot be known simply by looking at the solutions’ color. However, with some solutions, the color of the solution changes as the concentration changes. In these cases, the solutions can be analyzed using a spectrophotometer (Figure 1a). Inside a spectrophotometer, a beam of light passes through a monochromator, a device that changes the beam so that it is made up of only one wavelength of light. This modified beam travels through the sample to be tested, which is held in a cuvette, a thin glass tube. A sensor on the other side of the sample detects the light, and the device calculates the amount of light that is transmitted and the amount absorbed by the solution (Figure 1b). In this experiment, you will create copper (II) sulfate solutions of known concentrations, then test their absorbance using a spectrophotometer. You will use your data to create a graph of concentration versus light absorbance. Then, using the graph you created, you will determine the concentration of an unknown solution of copper (II) sulfate. Time Required 60 minutes 74 © 2011 Facts on File. All Rights Reserved. 11. Solutions and Spectrophotometry 75 digital status readout .

• Hoá học
• Chemistry experiments
• Microscale percent composition
• Levels of sugar
• Thin layer chromatography
• The rate of rusting
• Finding molar mass
• Exothermic reactions
• In this workbook
• experiments are elaborated using small scale glassware and equipments from a Small Lab Kit
• developed at the Department of Chemistry
• Faculty of Science
• Chulalongkorn University in Thailand
• This Small Lab Kit was created as a result of the research project entitled “Chemistry Laboratory Based on Chemical Safety and Pollution Minimization” sponsored by Thai Research Fund (RDG 3 07 2543)
• One of the outcomes of this project is the organic laboratory book entitled “Organic Chemistry Laboratory Based on Chemical Safety and Pollution Minimization” written in Thai by professors from 7 universities in this project
• They compiled
• adjusted and tested the experiments taken from several traditional organic chemistry laboratory books using the prototype of Small Lab Kit
• Currently
• some selected experiments from this Thai organic chemistry laboratory text have further been modified
• rewritten and edited in English as appeared in this workbook
• Some experiments ar
• The smell of an ester
• The chemistry of toothpaste
• Water softeners
• Lewis structures
• Making soap
• Hydrogen peroxide
• The golden book of chemistry experiments
• chemical analysis
• the overall chemical analysis
• chemical analysis of materials
• University of Edinburgh
• Professor of Chemistry
• chemistry
• chemistry document
• ebook chemistry
• chemistry specific study
• chemistry research
• Journal of technology and science education
• Contextualizing technology in the classroom via remote access
• Using space exploration themes
• Scanning electron microscopy
• Tools to promote engagement
• Multidisciplinary geology chemistry experiments
• Assessment tools
• Chemistry teaching
• Experimental competence
• Experimental science
• Developing students' qualities and capabilities
• chemical substances
• Naming and indexing
• chemical formulae
• molecular structure
• chemistry journals
• Vietnam Journal of Chemistry
• Structure elucidation of seven steroids from Sinularia conferta
• Structure elucidation of seven steroids
• The methanol extract
• The soft corals Sinularia conferta
• Experiments and comparison with reported data
• Steroids from the blood cockle Anadara granosa
• The blood cockle Anadara granosa
• Various chromatographic experiments
• BMC Chemistry
• Malus pumila fowers
• Three level orthogonal design experiments
• Tyrosinase during
• HPLC analysis
• Cross linked polycation
• Shale oil
• Anti swelling experiments
• Thermogravimetric analysis
• Journal of Chemistry
• Impurity profiling
• LC DAD HESI MS n
• Design of experiments
• Chromatographic conditions
• Active pharmaceutical ingredients
• Pharmaceutical contaminant of diethylstilbestrol
• Saponin and Brij 35 surfactants
• Natural clinoptilolite
• Batch and fixed bed studies
• Synthesis procedure
• Electrochemistry experiments
• Supplementary information
• Electrochemical studies
• Current density
• Electrodeposited nickel coatings
• Electrochemical experiments
• Cyclic voltammetry
• Surface morphology