Purpose and background The purpose of this lab is to determine the mass of anhydrous salt and H2O in a hydrate solution to calculate the empirical formula of the hydrate. To make this determination, the H2O in the hydrate is driven off to calculate the mass of the water and anhydrate. By driving off the H2O, the anhydrate will be left behind in the evaporating dish and may even change color or texture. The H2O in the hydrate is run off through the process of evaporation, where a liquid is heated to its boiling point and extracted from the substance in the from of vapor. The ratio of moles in a hydrate is one mole of anhydrous salt to one mole or greater whole number of H2O. The empirical formula of the hydrate is calculated through the use of properties of moles, molar mass, and conversion formulas. The mole is a unit which equates to the molar mass of one atom or Avogadro's number, 6.02 * 10^23. Using the molar mass of H2O and the anhydrate, the mass of the substances are converted into moles and written as an empirical formula. Procedure …show more content…
Weigh an evaporating dish and record the mass. Add ⅔ of a teaspoon to the evaporating dish and record the mass of the evaporating dish with the hydrate. Place the evaporating dish on the iron gause and heat the hydrate on low for two minutes, then high for five. Take the evaporating dish off the heat, let it cool, and record the mass of the evaporating dish and anhydrous salt. Repeat steps four and five. Determine the molar mass of the anhydrous salt and H2O to calculate the number of moles of each in the
the mass and initial temperature of the water. Next, impale the food sample on the needle. Next, light
I did accomplish the purpose of the lab. First, I determined the percentage of water in alum hydrate, and the percentage of water in an unknown hydrate. The results are reasonable because they are close to the example results. Second, I calculated the water of crystallization of an unknown hydrate. Furthermore, I developed the laboratory skills for analyzing a hydrate.
The first step that we took to accomplish our goal was to put on our safety goggles and choose a lab station to work at. We received one 400ml beaker, one polyethylene pipet, two test tubes with hole rubber stoppers, two small pieces of magnesium (Mg), one thermometer and a vial of hydrochloric acid (HCl). We took the 400ml beaker and filled it about 2/3 full of water (H20) that was 18 OC. Then we measured our pieces of Mg at 1.5 cm and determined that their mass was 1.36*10-2 g. We filled the pipet 2/3 full of HCl and poured it into one of the test tubes. Then, we covered the HCl with just enough H2O so that no H2O would be displaced when the stopper was inserted. After inserting the stopper, we placed the Mg strip into the hole, inverted the test tube and placed it in the 400ml beaker. HCl is heavier than H2O, so it floated from the tube, into the bottom of the beaker, reacting with the Mg along the way to produce hydrogen gas (H2). We then measured the volume of the H2, cleaned up our equipment and performed the experiment a second time.
I am going to carry out an experiment to measure the change in mass of
Experimental Summary: First, my partner and I put the marshmallow and cheese puff on T-pins and used the Electronic Balance to measure the mass of each of them. Next, we put 100 mL of water in the 100 mL Graduated Cylinder and poured it into the 12 oz. soda can. We measured the temperature of the water with the thermometer. After
In a Styrofoam cup, record the temperature of the 200 ml of cold water. This is 200 g of water, as the density of water is 1 g/ml.
The composition of water in magnesium sulphate pentahydrate using measured values is 46.0% water and 54.0% magnesium sulphate. The composition using defined values is 51.12% water and 48.83% magnesium sulphate. The hypothesis for the value of x was 6, and the experiment conducted also resulted in the value of 6 for the number of water moles to magnesium sulphate. However, the hydrated salt has 7 moles of water to 1 mole of magnesium sulphate, creating magnesium sulphate heptahydrate. This shows that there were experimental errors when conducting the experiment. One of the possible reasons why the calculations resulted in a different number was due to the hygroscopic nature of magnesium sulphate. As it is hygroscopic, the ionic compound continuously
Quickly and carefully transfer the heated metal from the test tube to the water in the calorimeter.
Rinse your beaker thoroughly to wash any excess powder. 12. Repeat steps 7-11 3 more times for reliability. To make sure the temperature still stays hot by continue heating the water a little bit using the hot plate. 13.
7.) After you have heated them to the right temperatures, pour the excess water into a dry evaporating dish. ( Be sure not to get any of the substance in your solution. )
It is essentially using the the mass of the product to figure out the original mass that we are looking for. Thus, the purpose of our experiment was to compare the final mass in our reaction to the initial mass and determine the change in mass. In our experiment, we utilized the hydrate cobaltous chloride. Hydrates are crystalline compounds in which one or more molecules of water are combined with each unit of salt. Cobalt (II) chloride hexahydrate is an inorganic compound which has a deep rose color in its hydrated form.
In a 100ml beaker place 50mls of water, measure the temperature of the water and record this initial temperature onto a table. Set the timer and add one teaspoon of Ammonium Nitrate to the water, stir this continuously until the Ammonium Nitrate has dissolved.
1. Obtain a clean, dry crucible and lid, then heat them for approximately 5 minutes over a Bunsen burner
= == In my investigation to find out how salt solution concentration affect the mass of potatoes, I will investigate how much the mass of a potato changes if I leave it in a beaker of water with a specified salt concentration for half an hour. I will change the salt concentration after each experiment. Background Knowledge --------------------
In this experiment three different equations were used and they are the Stoichiometry of Titration Reaction, Converting mL to L, and Calculating the Molarity of NaOH and HCl (Lab Guide pg. 142 and 143).