Finding a Material's Specific Heat Capacity
Skill A
Aim:
The aim is to accurately find the specific heat capacity of a material
given a certain mass of that material and other experimental
equipment. The specific heat capacity of a substance is the heat
energy required to raise one kilogram of the material by one Kelvin or
one degree centigrade - it is usually measured in J kg-1 K-1. The
experimental technique and results will be analysed. The purpose is to
be able to conclude the reason for certain materials having higher or
lower specific heat capacities than others and to discuss these
reasons scientifically. Perhaps, during the course of the experiment,
means could even be devised to reduce energy-loss when heating
substances.
In addition, it should be ensured to be an entirely fair test and the
results we achieve must be reliably accurate and trustworthy.
Everything will be controlled as best as it can be under the
circumstances so a viable conclusion can be generated at the end, the
correctness of which can be analysed.
Planning and method:
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Before any experimental data was gathered, a preliminary experiment
was carried out to aid the planning process, practise the procedure
and to predict any difficulties that may be encountered. The most
successful methods of insulation were tried out to optimise the
accuracy of the experiment by minimising heat loss. It was decided
that the specific heat capacity of copper would be found. In addition,
the apparatus that would be used could be decided after comparative
tests and after assessing the sensitivities and accuracies of the
instruments. Because of the preliminary work, it was decided that the
material being heated would be insulated to reduce heat loss as much
as possible and then put in a measured volume of distilled water, the
temperature of which would be monitored. Hence, with the knowledge of
the specific heat capacity of water at appropriate temperatures, the
amount of energy wasted in order to heat the water could be calculated
First, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder. This water was then poured into the styrofoam cup that will be used to gather the hot water later. The water level was then marked using a pen on the inside of the cup. The water was then dumped out, and the cup was dried. Next, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder, and the fish tank thermometer was placed in the water. Once the temperature was stabilizing in the graduated cylinder, the marked styrofoam cup was filled to the mark with hot water. Quickly, the temperature of the regular water was recorded immediately before it was poured into the styrofoam cup. The regular/hot water was mixed for a couple seconds, and the fish tank thermometer was then submerged into the water. After approximately 30 seconds, the temperature of the mixture leveled out, and was recorded. This was repeated three
mole of any gas will occupy a volume of 24 dm³.’ We will need this to
Although Black’s discovery of carbon dioxide was said to lay the foundation for modern chemistry, it wasn’t the only discovery he is credited for. He was the first to conclude that heat and temperature were two different things. Black used water as a universal substance to show that heat is energy, in which may be transported through moving and colliding molecules and the idea that temperature is the measurement of the average motion or kinetic energy of the molecules. He demonstrated this with a bucket of ice monitored by temperature constantly. The ice continually melted, but the temperature remained constant. Black is also well known for his discovery of latent heat, the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature. Latent heat was con be expressed in two ways: the heat can be absorbed if the change involves solid to liquid or liquid to gas or the heat can be released if the change involves gas to liquid or liquid to solid. Black took this idea and developed “specific heat”, in which is defined as the measured amount of heat required to raise the temperature of a substance by a specified number of degrees.
By adding fresh cold water it should cool the copper calorimeter. By making sure I do these checks before I do the experiment means that I should be able to get accurate results as the test will have been run fairly and hopefully successfully as there should not have been anything gone wrong. To make sure all the measurements are correct, I will also run checks. These checks when recording the data are. Make sure to check the thermometer to see what temperature the water is at the start, so I am able to see what it has to be when its been heated by 10 degrees.
rates. The bigger the atom the more slowly it will take to heat up and
Specific heat capacity of aqueous solution (taken as water = 4.18 J.g-1.K-1). T = Temperature change (oK). We can thus determine the enthalpy changes of reaction 1 and reaction 2 using the mean (14) of the data obtained. Reaction 1: H = 50 x 4.18 x -2.12.
Tf-Ti). Next, subtract the initial temperature, 25 degrees from the final temperature, 29 degrees putting the change in temperature at 4 °C. To calculate the heat absorbed by the water in calorimeter, use the formula (q = mCΔT). Plug in 50 mL for (m), 4.184 J for (C) and 4 °C for the initial temperature (ΔT), then multiply.
The objective of this experiment was to identify a metal based on its specific heat using calorimetry. The unknown metals specific heat was measured in two different settings, room temperature water and cold water. Using two different temperatures of water would prove that the specific heat remained constant. The heated metal was placed into the two different water temperatures during two separate trials, and then the measurements were recorded. Through the measurements taken and plugged into the equation, two specific heats were found. Taking the two specific heats and averaging them, it was then that
OFHC copper refers to oxygen-free, high conductivity copper alloys, which typically are types of pure copper alloys. OFHC are metallic materials of the group nonferrous alloys, which is known for it is high conductivity of electrical and thermal ability. OFHC produced by the direct conversion of selected refined cathodes and castings under carefully controlled conditions to prevent contamination of the pure oxygen-free metal during processing. The method of producing OFHC copper ensures extra high grade of metal with a copper content of 99.98%. With so small a content of extraneous elements, the inherent properties of elemental copper are brought forth to a high degree. The most common OFHC copper alloys are C10100 (OFE) where it has 99.99% of copper and less 0.2%of oxygen and CAD10200 were it has 99.95% and around 1.5 ppm of oxygen. The companion that could be found in OFHC alloys are; Copper with 99.98% of weight, Oxygen with less than or equal to 1.5 ppm, Antimony with less than or equal to 0.1 ppm, Arsenic with less than or equal to 0.1 ppm, Nickel with less than or equal to 10 ppm, Manganese with less or equal to 0.5 ppm, Tin with less or more than 2 ppm, Zinc with less than or equal to 1 ppm, Tellurium with less than or equal to 2 ppm, Sulfur with less than or equal to 15 ppm, Silver with less than or equal to 25 ppm, Selenium with less than or equal to 3 ppm ,Phosphorus with less than or equal to 3 ppm, Bisumasu with less than or equal to 0.1 ppm, Cadmium with less than or equal to 0.1ppm,lead with less than or equal to 1ppm and Iron with less than or equal to 1 ppm . OFHC used mostly in building constructions and as electronic products.
Our project for the unit 2 test will be a candle and water demonstration. This will show the different relationships between temperature, pressure, and volume.
The precision of a 50 ml beaker, 25 ml grad. cylinder., and a 25 ml pipette were determined by transferring each type to a tared 50 ml beaker. The density of copper was determined through volume displacement in water. The pipette was fond to be the most precise with a mean volume of 24.843±0.184ml. While the 25 ml cylinder had a volume of 24.601±0.708 ml and the 50 ml beaker had a volume of 24.074±1.98 ml. The density of copper was found to be 9.190±0.836, with an accuracy of 2.567%. The difference in density measurements could be due to human error or temperature differences.