Heat Capacity Lab

The boiling point elevation constant for water that was experimentally determined in this analysis was 0.4396 °C/m, which was derived from the slope of the trend line in Figure 2. This is slightly lower than the constant provided in lecture of 0.51 °C/m. This could be due to further evaporation of water from the solutions tested via refractive index after the boiling temperature was recorded.

The objective of this lab was first to convert the mass of a compound to the number of moles and number of molecules and then determine the concentration of salt and its component. The first thing we did was get the mass of an empty container by using a scale and it came out to be 16.87g. Next thing we did was pick a substance which in this case it was Potassium Chloride and placed it on the scale to get a total mass of 31.20g. The container the Potassium Chloride was in only had a mass of 16.87g which means that the mass of the substance was 14.33g. To convert the mass to the number of moles we took the amount of the substance 14.33g and divided it by the mass of Potassium Chloride 74.55g and figured out that the number of moles was 0.192.

Purpose: To find the relationship between the mass and the volume of the four samples.

The percent mass of each component of the mixture was 23% iron, 61% sand, and 8.7% salt.

Place the test tube containing cold water in a test tube clamp and hold the test tube above the burning alcohol. Observe the outside of the test tube for evidence of product formation.

2. Used a test tube clamp to held the test tube and gently heated the tube in a laboratory burner flame for about 30 seconds.

Submerge the graduated cylinder in the plastic tub so that it is completely filled with water. Hold the open end of the graduated cylinder and move it vertically upside-down where the open end of the graduated cylinder is still submerged in the plastic tub. Clamp the graduated cylinder the ring stand of the lab table to keep it in place. perforate a hole in the top of the rubber cork for the solution container. Cut a straw the length of about four inches. place the straw inside of the rubber cork hole. Set up your timer for two minutes.

We calculated the specific heat of metal one to be 0.39 J/g℃ which correlates to the exact specific heat capacity of element 30 Zinc. For metal two, we calculated the specific heat capacity to be 0.38 J/g℃ which was close to the actual specific heat of element 23 Iron. The specific heat capacity of Iron was 0.45 J/g℃. Our inaccuracy could be a result of not reading the thermometer as accurately as we could have. To improve yield in the future, we could make sure we record more accurate temperatures.

This lab was to see chemical reactions with different liquids. This was important to find the unknown substance. The controlled variable was the unknown powder, since it doesn’t change. The independent variable was the liquids. These liquids were vinegar, iodine, and water. Lastly, the dependent variable is the chemical reactions. The reaction was affected by the different liquids. If the liquids are changed then the chemical reactions will be different, because they have different properties, causing the atoms to bond differently.

The metal that was assigned to us was Lead. In part 1 we had to find the Specific heat of the metal and we used the equation -(mass of water) (4.18 J/g°C)(∆T water)/(mass of metal0(∆T metal). We concluded that The Specific heat of the Metal was 0.17 J/g°C. To be able to find the after we determine the specific heat we had to find the Calculation of the slope.

In order to conduct the experiment, the first step is to measure the aluminum pieces in a tared weigh boat in which the mass lies in between 0.9 to 1.2 grams then transfer them into a 250mL beaker. Then, pour the 50 mL of 1.4 molarity of potassium hydroxide into the 250mL beaker with the aluminum pieces as it’s on the hot plate. Thirdly, set up the aspirator and connect it to the apparatus; then apply a damp filter paper to the büchner funnel when the solution is completely done mixing with the aluminum pieces. Turn on the vacuum and pour the solution through the filter. Once, that is complete, move the filtrate to a clean 250 mL beaker and clean the flask using 10 mL of distilled water and emerge the clean flask with the filtrate.

The scientist’s main goal in this experiment is to see which metal will conduct the most thermal energy out of the three. The scientist will try and find a clear answer to this problem by placing two cups of water one cold and one hot to see which metal transfers the most

Measure and fill the graduated cylinder with 10 ml of HCl, and transfer to the test tube labeled A. Repeat step 2 for test tube labeled B and C. Add 3 drops of universal indicator to each of the test tube A, B and C. Add as many drops of Milk of Magnesia as you need to test tube A, swirling around between drops, until the color is neutral by comparing it to the control test tube of water. Make sure to stop at the

4.Measure 35mL of warm water and add them into each of the 4 test tubes at about roughly the same time. It is essential that the water is warm. Do not seal the test tube.

Place the beaker on the hot plate, place the thermometer in the beaker and set the hot plate to 5oC.