Physical Change Lab Report Essay

The hypothesis is correct. Potassium chloride mixed with silver nitrate creates a white precipitate. Barium

The experiment is to observe a variety of chemical reactions and to identify patterns in

Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.

Step 4: Place the test tubes into separate coffee cups to maintain the upward position. Add 2 mls of the catalase solution to each of the test tubes and then place tubes1, 2, and 3 in the conditions described above. For test tube 4, fill the coffee mug half full of boiling

Procedure: In this experiment, various chemicals were mixed together, to determine a reaction. Using two drops from chemical 1 and two drops of chemical two, unless otherwise stated, then recording the type of physical reaction or color changes that occurred.

A physical change includes a change in the material without affecting its composition, such as the physical state change. However, a chemical change includes the change in the composition of the substance. The change in color, formation of a gas or a solid product, and the production of energy are the evidences of a chemical reaction, thus, of a chemical change.

The purpose of this lab is to test substances and to determine the physical and chemical properties of substances.

When the red Co(NO3)2*6H2O crystal was added to the white NH4 crystal, and water was added to dissolve, the solution turned blue in color. As the solution was nixed, the color changed to that of a blue-purple and a blue precipitate formed. When the 6 M NH3 began to be added, the color shifted to dark purple color after 15 mL of ammonia and the amount of the precipitate was less. After 20 mL of ammonia, the solution became a red brown with very little of the blue precipitate. After 30 mL of ammonia, the solution was similar in color to an iodine solution, a dark brown-red, almost black in color. At this point there was no visible precipitate on the surface of the solution. After 40 mL of the ammonia had been added, the solution was the same iodine like color as before. When closely examined, there was a black precipitate that had settled on the bottom of the beaker. At this point, hydrogen peroxide, 3% H2O2, was added to solution. After 4 mL of the H2O2 was added, the solution was the same color and the precipitate had not changes. After 8 mL of the H2O2, there was not noticeable change. After 12 mL of the H2O2, the solution was slightly redder in color but the precipitate had not changed. After 15 mL of H2O2, the solution was the same color and no changes had occurred to the precipitate. At 17 mL, the solution began to effervesce slightly, though there

When the zinc was dropped in the hydrochloric acid, the substance began bubbling vigorously, forming a precipitate. Eventually, the zinc dissolved completely. After the lit wooden splint broke the surface of the test tube, there was a loud popping noise. The gas that was released was hydrogen from the acid and the popping noise was a result of the Hydrogen being burned up by the fire creating a small explosion. Two chemical changes occurred in this test: one with the formation of a precipitate (a textbook sign of a chemical change), and the other when the explosion

Product bubbled upon addition to the hydrochloric acid; liquid turned cloudy ¡V precipitate was present; zinc sample disintegrated slowly and turned black in color.

| NaHCO₃ reacts with the hydrochloric acid by heating up violently, bubbling, dissolves, and new gas formation

3. The “new” substances that were formed as a result of chemical change were many. When I took the candle and lit it, it burnt and formed smoke. When I took the wooden split and lit the paper on fire, the color around the green paper changed to be brown, burnt and changed into ashes. Also, I poured Hydrochloric acid and magnesium ribbon in a test tube and it started bubbling and it heated up in the bottom.

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

A few more important terms to keep in mind when doing a lab with chemical and physical changes are

When the sulfuric acid was added to copper (II) oxide, the solution turned blue. This was due to the formation of aqueous copper (II) sulfate, which produced the copper ions to change the color of the solution.