The calorimeter was designed in 1780 by a chemist named Antoine Lavoisier with help from a mathematician by the name of Pierre Simon de Laplace. Now a widespread tool, we will be using the calorimeter, and our knowledge of equations to find the specific heat of zinc and aluminum. OBJECTIVE/GOAL In this experiment we will Measure the mass and temperature of water in a calorimeter Heat a metal sample of a known mass to a specific temperature Calculate the change in water temperature caused by adding the hot metal sample Calculate the specific heat of the metal using your mass and temperature data PROCEDURE 1. Prepare a data table as directed in the Analysis. Safety goggles and lab apron must be worn for the experiment.
10. Repeat the procedure for a second metal. Analysis: Our data | Trial #1 | Trial | Mass of zinc | 1.99g | 4.01g | Mass of water in Calorimeter | 45g | 45g | Temp. of water in Calorimeter | 20°C | 21°C | Temp. of boiling water | 100°C | 100°C | Peak temp.
The Empirical Formula of an Oxide, Purpose: The purpose of this lab was to determine the empirical formula of magnesium oxide. To do this, we measured the weight of the magnesium before the reaction with oxygen, and then measure it after it had bonded with the oxygen. After the mass of the items were collected, the data was calculated in empirical formula. Background: The empirical formula of a compound is the whole number ratio of the elements in a compound. For example, the empirical formula of water is H2O meaning for every 1 O atom there are 2 H atoms.
The only ore that contains chromium is the mineral chromite, which is iron magnesium chromium oxide. Chromite has a high melting point and a stable crystalline structure. The purpose of this experiment is to determine the chemical content of an unknown metal ore sample to confirm that the unknown sample is mineral chromite. The content of the unknown sample will be determined by the use of a type of extractive metallurgy that uses the chemistry of an aqueous solution to remove metals from salts, minerals, and ores. This type of extractive metallurgy is called hydrometallurgy.
In part one of the lab we used a micro scale technique to derive an activity series for metals. With the use of this technique we measured the same amount of different metal nitrate solutions into each well. Then we placed a piece of metal in the other metal nitrate solutions. With the data we recorded we resulted our activity series for the metals. We resulted that lead, silver, and copper are the strongest oxidizing agents, and that magnesium and zinc are the weak oxidizing agents.
The pre-1983 penny was made of an alloy of copper and zinc. An alloy is “a substance that has metal characteristics and consists of two or more different elements”. (Coordinated Science, pg.1005) Our objective is to find the metal used inside a post-1983 penny. The accepted value of the density of a post-1983 penny is 7.05g/cm3. “Density is the mass per unit volume of a material”.
Balance Lab Title: Get familiar with a Centigram Balance Purpose: The purpose of this lab was to use the Centigram Balance and the Electronic Balance to measure the weight in grams of a copper slug, a 100ml Beaker, and an unknown substance. The experiment was to help me get familiar with the weighing of certain materials and the different types of weighing, including direct weighing and weighing by difference. Materials: 2 Copper slugs, 2 100ml Glass Beaker, 2 Centigram Balances, 2 Electronic Balances, 2 unknown weights. Method: First, measure the copper slug using the centigram balance, then put the slug inside of a 100ml Beaker and measure its weight and record the value in the table below. Then measure the Beaker by itself and calculate the weight of the slug by difference.
Procedure: Throughout this lab we were finding the physical properties of substance B. We found the boiling point, freezing point, density and solubility in water, hexane and Alcohol. We started by finding the boiling point
Part C: Density of Sodium Chloride (NaCl) Solution, a sample of NaCl was obtained and measured using a 100mL beaker and a 10mL pipet to determine the concentration of the solution. In order to obtain the appropriate result, a calibration graph and density measurement was used to determine the concentration of the sodium chloride solution. In conclusion, based on the water temperature of 21.8°C in part A’s graduated cylinder experiment obtained, it was determined that the average density was .0973g/mL with a percentage error of 2.5%. When graphed the measurement was equal to Y=0.988x. Part B: The graduated pipet’s average density at 22.3 °C was determined to be 0.9785g/mL with a percentage error of 1.89% shows the graduated pipet to be more accurate and precise.
Experimental Procedure: 250 mL of the copper solution was made by creating 100 mL of the solution, reacting CuO with HNO3, and then diluting to the mark of 250 mL. Using this stock solution, different concentrations were made and placed in the sprectrometer for observation. The absorbances and transmittances were recorded for use when identifying the amount of the color-absorbing copper ions later. A graph was plotted of Absorbance v. Molar Concentration easily see the results of the experiment. Pre-Lab Questions: 1.