Calorimetry Lab

The mass of salt (.26 grams) was then divided by the total mass of mixture (3 grams) and then multiplied by 100 to get 8.7% salt. The mass of sand was determined by subtracting the 100mL beaker with filter paper and sand (54.57 grams) by the the empty 100mL beaker with filter paper weighing 52.74 grams, to get 1.83 grams of sand. The mass percent of sand was determined by dividing the 1.83 grams of sand by the mass of mixture (3 grams) and multiplying by 100 to get 61%

8. Repeat step 7 with H2SO4, except that you should use a 10 mL graduated cylinder of H2SO4 and adding 15 mL water.

Weigh the beaker with water in it, record this value in Data Table 1 and subtract the mass of the beaker to get the mass of the water. Record this value in Data Table 1.

16) Heat some of the hexane to boiling and place the solid to be crystallized into an Erlenmeyer flask.

9.Repeat the procedure with a new mass of baking soda. Before beginning, rinse the reaction vessel with water. Refill the graduated cylinder with water. Check water level in collection box so it has room for the water from the graduated cylinder.

Place the 1%, 10%, and 50% NaCl cells into each of the three 400mL NaCl solutions. 7. Wait 40 minutes. 8. Remove the cells, one by one, and weigh.

XIII. Carefully remove the copper metal from the filter paper onto the watch glass. (with a spatula) Place a 400 ml beaker on a hot plate contained with water. Carefully place the watch glass before the water boils to dry the copper metal. (Use the tongs to handle the hot watch glass)

Once the filter paper is in the funnel, moisten it with distilled water. Position beaker 2 underneath the funnel. In order to begin filtering the mixture, decant the supernate into the funnel, guiding it with a stirring rod. With distilled water, place the remaining solid in the funnel. Once all of the solid is in the funnel, add some distilled water to the funnel, draining into beaker 2.

A pH strip was used to indicate that any excess base was no longer within the crystals. 7. The crystals were then weighed on a scale and the mass was recorded. 8.

After doing so, ten milliliters of the subsequent 'contaminated' mix were set aside in one of the 100 milliliter beakers. Into the remaining solution in the 250 milliliter beaker was added the ten grams of alum, which was then stirred for two minutes with a wooden stir stick, then was set aside for fifteen minutes.

Crystals were collected in a Buchner funnel, washed with alcohol, then ether, then transferred into a sample tube for storage.

Measure 500ml of tap water in the 500cm3 beaker, then measure 5g of sodium hydrogen carbonate using the 50cm3 beaker and weight scale and place in the beaker of water, using the glass rod to dissolve it into the mixture.

This was done to separate the liquid from the crystals themselves. The beaker was twice rinsed with 50% ethanol and 10 mL water to make sure that there were no remaining crystals. The precipitate was left to dry, and an empty watch glass was measured (55.5671 grams) with the use of a scale. Once completely dry, as to avoid residual liquid from skewing the data, the precipitate was transferred onto the watch glass and measured once again. The final weight of the watch glass and the precipitate was 71.

I allowed it to cool in an ice-water bath. Using the vacuum filtration, I collected ASA crystals. During this process, only the ice-cold distilled water was used. In order to wash the crystals, I used approximately 10mL of water. I transferred the crystals to a watch glass that has already been pre-weighed.

precipitate; then pour over the solid in the funnel. Finally, pour two 10-mL portions of