Unit 6 C and D Assignment Project for Applied Science

Unit 6 C and D Assignment Project for Applied Science Project Research and Planning – Heat Loss through Cooling Curves Unit 6: investigative Project C: Safely undertake the project, collecting, analyzing and presenting the results D: Review the investigative project using correct scientific principles Summary/abstract: In this report, I investigated the differences in heat loss in a cooling curve. I research the different ways of how to investigate this. I decided on one final method and carried out the experiment. This study was done by following through with an investigation and experiment. The results were recorded in tow formats. A table and line graph. The main findings of our experiment were that paraffin wax cools at a faster rate compared to stearic acid. And this depended on the molecular bonding of the two substances. The significance of these findings is now you know when and how to use these elements depending on what you want to use them for. Literature Review: Cooling curves: A cooling curve is a graph illustrating a substance's temperature variation over time as it cools. The gradient of the cooling curve is proportional to the heat capacity, thermal conductivity, and external temperature of the substance. The more heat required to cool a substance, the slower it cools, and so the smaller the gradient of the curve. The greater the thermal conductivity, the more quickly heat is transmitted, and the substance cools. The lines are curved because the temperature difference between the substance and its surroundings decreases as it cools. This reduces the rate of heat transmission out of the substance, hence reducing the cooling rate. (IsaacPhysics 2019) For most pure substances, phase transitions occur at specific temperatures. The temperature remains constant throughout the phase change, as the energy produced by making new bonds in the substance compensates for the cooling. As a result, phase transitions are presented as horizontal lines. (Isaacphysics 2019) Cooling curve of a pure substance: (isaacphysics201 lOMoAR cPSD| There are 4 mechanisms of heat loss. Evaporation, radiation, conduction, and convection. Evaporation: Evaporation is the process by which an element or compound changes from a liquid state to a gaseous state below the point of boiling; more precisely, it is the process by which liquid water enters the atmosphere as water vapor in the water cycle. Evaporation of water from wet skin (sweating). When your clothing is wet, you will also lose heat through evaporation and respiration (breathing) if your body temperature exceeds 99°F (37°C). During vigorous exercise, the body sweats out 85 percent of its heat. This is a particular type of heat loss. (mottchildren2012) Radiation: This natural process of heat transfer away from the body occurs most frequently when the air temperature is less than 68°F (20°C). Radiation accounts for 65 percent of the body's heat loss. Radiation is a method of losing heat via infrared rays. This is the process by which heat is transferred from one object to another without physical contact. For instance, the sun radiates heat to the earth. (unm2018) Conduction: Conduction is the process by which heat is lost when an object or body comes into physical contact with another object or body. If you sit in a metal chair, for example, the heat from your body will transfer to the cold metal chair. Heat is lost when the air temperature is below 68°F (20°C). The body loses approximately 2% of its heat via conduction. However, because water conducts more heat away from the body than air does, heat can be rapidly lost from the body when submerged in cold water. (sciencedirect2020)