物化实验（Physicochemical experiment）.docVIP

物化实验（Physicochemical experiment） Thinking question Experiment 1 Determination of heat of combustion 1. what are the systems in this experiment? What are the circumstances? Is there a heat exchange between the system and the environment? What effect does the heat exchange have on the experimental results? How to correct? Note: the bucket internal material and space for the system, in addition to the internal tub material and space calorimeter rest environment, heat exchange between the system and the environment, the heat exchange will affect the accuracy of determination of heat of combustion, the Reynolds correction curve correction to reduce its influence. 2. why are solid samples pressed into sheets? How are the amounts of naphthalene and benzoic acid determined? Tip: pressure into a sheet to sample the full combustion of naphthalene and benzoic acid; Determination of the amount of little error is large, too much is not fully burning, can determine the maximum amount of the samples according to the volume of oxygen bomb and internal oxygen pressure. 3. what are the causes of sample burning and burning? Tip: press too tight, burning wire will cause burning into a pill; pressing too loose, lack of oxygen can cause burning as. What are the main factors that affect the results of the 4. test analysis? What are the key factors for the success of the experiment? It is pointed out that whether the sample is sufficiently burned and the heat exchange between the system and the environment is the main factor affecting the results of this experiment. The key to the success of this experiment is the appropriate amount of the drug, the proper elasticity of the tablet, and the correction of the Reynolds temperature. 5. what should be paid attention to when using oxygen cylinders and oxygen reducers? Tip: read the physics chemistry experiment textbook P217-220 Therefore, the relative molecular weight of naphthalene is low. Experiment four drawing of gas liquid equilibrium phase