LAB_11 - Calorimetry

# LAB_11 - Calorimetry - Lab 11 Calorimetry "Iron rusts from...

This preview shows pages 1–3. Sign up to view the full content.

Lab 11 125 Calorimetry Summary Calorimetry encompasses the class of experimental methods associated with measuring quanti- ties of heat and their associated temperature changes. Calorimetry forms one of the principle experimen- tal foundations of thermodynamics. Experimentalists use calorimetry to quantify the relationship between temperature and energy content in almost endless an variety of chemical, biological, metallur- gical and ecological systems. This experiment provides an introduction to the fundamental principles and techniques of calorimetry, by measuring the heat capacity and latent heat of various materials. Educational Objectives After performing this experiment, a student should be able to: 1 . Construct and calibrate a simple calorimeter and study sources of error. 2 . Measure the heat capacity of various liquids and solids. 3 . Measure the heat of fusion. Background Information - Calorimetric Quantities Heat Capacity - When heat or energy is added to any material the temperature of that material will usually rise. In many circumstances, the temperature rise T for a laboratory specimen is directly proportional to the quantity Q of heat added. The heat capacity C of the specimen is defined as the ratio of the heat added Q to the temperature change T . That is: The units of heat capacity are Joules per ºC . Notice that the heat capacity depends on the size of the specimen. The heat capacity of a lake, is much larger than the heat capacity of a cup of water, even though both specimens consist of the same substance H 2 O. "Iron rusts from disuse; stagnant water loses its purity and in cold weather becomes frozen; even so does inaction sap the vigor of the mind." - Leonardo da Vinci (1452 - 1519) (1) C Q T =

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Lab 11 126 Specific Heat - In contrast, the specific heat of a substance is defined in a way which is indepen- dent of the size of the sample. The specific heat ρ of a substance is the amount of heat Q that must be added to raise the temperature of 1 gram of the substance one degree Celsius. The units for specific heat are thus J/(g ºC) . In this lab, the heat capacity C and specific heat of various substances (water and unknown liquids) will be determined. The specific heat of water has been measured to be 4.184 J/(g ºC) . Latent Heat - The three most common states of matter are solid, liquid and gas. In any kitchen for example, one may find H 2 O in any of the three states (or phases) ice, water and steam. When energy is continually added (or removed) from a substance, eventually a state or phase transition temperature will be reached at which the temperature does not change, but instead the state of the substance changes.
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 12/16/2011 for the course ENGR 102 taught by Professor Cattell during the Fall '10 term at Community College of Philadelphia.

### Page1 / 8

LAB_11 - Calorimetry - Lab 11 Calorimetry "Iron rusts from...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online