Eye Dropper And Calorimetry Lab Report Results

1. 100 + 273 K = 373 K 150 + 273 K = 423 K 960 L x 423 K / 373 K = 1,089 L 2.

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

Procedure: Filled each test tube with substances provided and subjected them to various conditions. These conditions included, heat, cold water, hot water, acid and basic additions and tested on litmus paper. The reactions were observed and documented at each step.

The purpose of this lab is to figure out the mass percentage of copper in a penny. Furthermore, by doing this lab we will practice using a spectrophotometer and review the names of equipment such as volumetric glassware, pipets, and volumetric flasks.

Weight 30 dry pre-82 pennies which get 89.77g, using 30ml initial volume measuring the volume of 30 pennies, record the data 10.0ml. Using equation Density= Mass/Volume, get the density of the pre-82 pennies is 8.98g/ml. Then calculate the error%=0.10%, and the deviation%=1.29%.

And finally into test tube 3, I pipetted 1.0 ml turnip extract and 4.0 ml of water. The contents of test tube 1 was poured into a spectrometer tube and labeled it “B” for blank. “B” tube was now inserted it into the spectrometer. An adjustment to the control knob was made to zero the absorbance reading on the spectrometer since one cannot continue the experiment if the spectrometer is not zeroed. A combination of two people and a stop watch was now needed to not only record the time of the reaction, but to mix the reagents in a precise and accurate manner. As my partner recorded the time, I quickly poured tube 3 into tube 2. I then poured tube 2 into the experiment spectrometer tube labeled “E” and inserted it into the spectrometer. A partner then recorded the absorbance reading for every 20 seconds for a total of 120 seconds. After the experiment, a brown color in the tube should be observed to indicate the reaction was carried out. Using sterile techniques, any excess liquid left was disposed

Chemical changes occurred in five out of the eight experiments completed in this lab. Although the main focus of experiment two was

The objective of the experiment was to observe different reactions with different chemicals. The experiments emphasized on the chemical changes occurring in acids and bases as well as color changes and bubble formations. The experiments allowed for a better understanding of the undergoing chemical changes in mixtures. Some mixtures instantly changed colors while others were transparent or foggy. Some mixtures produced thick color that created solids called precipitates. Mixtures KI + Pb(NO3)2 and NaOH + AgNO3 both produce noticeable precipitates after a while. It was interesting to see the different acidic and base reactions like the fuchsia color formation in NaOH + phenolphthalein.

The materials needed for this experiment included test tubes, a test tube holder, the unknown compound #202, 35mL beakers, gloves, safety goggles, ethanol (to clean equipment), stirrer (to mix solutions), the 15 possible compounds that are provided, pH strips, distilled water, wooden splints, spatula to get out unknown compound #202, waste bucket, Bunsen burner, graduated cylinder, 500mL beaker for the waste, plastic dishes to measure out compound and the scale.

In part II of the lab six small glass tubes were obtained in a test tube rack. Ten drops of distilled water were then added to test tube 1, five drops to tubes 2-4, and no drops in tubes 5 and 6. Five drops of 0.1M HCl were added to test tube 5 and five drops of 0.1M NaOH to test tube 6. Five drops of enzyme were then added to all tubes except tube 1. Tube 3 was then placed in the ice bucket and tube 4 was placed in the hot bucket at 80-900C for five minutes, the remaining tubes were left in the test tube rack. After the five minutes five drops of 1% starch was added to every tube and left to sit for ten minutes. After ten minutes five drops of DNSA were then added to all the tubes. All the tubes were then taken and placed in the

The first trial that contained 10 mL of NaOH and 10 mL of CH3COOH produced a ΔHrxn of -13.11 kJ/m. The second trial, which contained 15 mL of NaOH and 5 mL of CH3COOH resulted in a ΔHrxn of -7.864 kJ/m. Based on the literature value of NaOH CH3COOH, -57.5 kJ/m, we were off by 44.39 kJ/m in the first trial, and 49.64 kJ/m in the second trial.

The purpose of this experiment was to test the effects that temperature, pH, and substrate

Calorimetry is the science of measuring the change in heat absorbed or released during a chemical reaction. The change in heat can tell us if the reaction is either exothermic - it released or heat into surroundings, or endothermic - it absorbed heat from surroundings. The device used to measure calorimetry is a calorimeter. A calorimeter can range from very expensive lab ones to coffee styrofoam cups but they are all tightly sealed in order to prevent heat from escaping.

The first experiment begun by filling a 600-ml beaker, almost to the top, with water. Next, a 10-ml graduated cylinder was filled to the top with water. Once water was added to the beaker and graduated cylinder, a thumb was placed over the top of the graduated cylinder. This would ensure that no water was let out and no bubbles were let into the graduated cylinder. Next, it was turned upside down and fully submerged into the beaker. Then, a U-shaped glass tube was attained. The short end of the glass tube was placed into the beaker with the tip inside of the graduated cylinder. Next, a 50-ml Erlenmeyer flask was received. After, 10-ml of substrate concentration and 10-ml of catalase/buffer solution were placed into the flask. A rubber stopper was then placed on the opening of the flask. After adding these, the flask was held at the neck and spun softly

Objectives of the experiment The