Chemical Change Lab Report

Purpose: The purpose of this experiment is to observe chemical changes in common consumer products to determine if the chemicals are basic, acidic, or remain neutral when mixed with other chemicals.

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 mole is a convenient unit for analyzing chemical reactions. Avogadro’s number is equal to the mole. The mass of a mole of any compound or element is the mass in grams that corresponds to the molecular formula, also known as the atomic mass. In this experiment, you will observe the reaction of iron nails with a solution of copper (II) chloride and determine the number of moles involved in the reaction. You will determine the number of moles of copper produced in the reaction of iron and copper (II) chloride, determine the number of moles of iron used up in the reaction of iron and copper (II) chloride, determine the ratio of moles of iron to moles of copper, and determine the number of atoms and formula units involved in

A chemical reaction is when substances (reactants) change into other substances (products). The five general types of chemical reactions are synthesis (also known as direct combination), decomposition, single replacement (also known as single displacement), double replacement (also known as double displacement), and combustion. In this lab, the five general types of chemical reactions were conducted and observations were taken before, during, and after the reaction. Then the reactants and observations were used to determine the products to form a balanced chemical equation. The purpose of this lab was to learn and answer the question: How can observations be used to determine the identity of substances produced in a chemical reaction?

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

| Can see particles of both. When mixed with water salt dissolves and sand is left.After filter sand is left and salt-water goes through.After evaporations of salt-water, salt is only left in dish.

Purpose: The purpose of this experiment is to observe a variety of chemical reactions and to identify patterns in the conversion of reactants into products.

Table 2: Consists of color extract taken from a red cabbage for a natural indicator. The pH reading that was measured by using the pH meter and the result of the pH reading to determine whether the solution was acidic or basic.

The first example of macroscopic change I observed is the color change from the combination of Starch + I2. The second example of macroscopic chemical change is the sediment formed by the combination of MgS04 and NH3. The third example is the foam from the mixture of Na2CO3+ CH3COOH

Purpose: The purpose of this experiment was to observe the many physical and chemical properties of copper as it undergoes a series of chemical reactions. Throughout this process, one would also need to acknowledge that even though the law of conservation of matter/mass suggests that one should expect to recover the same amount of copper as one started with, inevitable sources of error alter the results and produce different outcomes. The possible sources of error that led to a gain or loss in copper are demonstrated in the calculation of percent yield (percent yield= (actual yield/theoretical yield) x 100.

A Cobalt-Amine-Halide compound is synthesized from cobalt (II) chloride hexahydrate. An orange-tinted solid is produced and is considered to be unknown since the specific ligand amounts are unknown. By determining the percent composition of various elements and compounds in the unknown, its true identity can be predicted. Chloride, ammonia, and cobalt are three examples of percent compositions determined to help narrow the selection of possible unknowns. Titrations using Na2S2O3 and HCl to determine percent cobalt and ammonia, respectively, are used. Silver nitrate is used to precipitate the chloride ions in the unknown, which can be measured to determine the percent composition of chloride

First, we started testing solutions such as Water, Sodium Phosphate (Buffer), and Sodium Chloride. The two control solutions that were used in experiment were HCl which is an acid and NaOH which is a base. The purpose of the two controls is to test and determine if NaCl is a buffer or not. When HCl was added to NaCl the pH decreased from 7.60 to 2.53 pH. The comparison of the pH change of NaCl and Na3PO4, shows that when adding acid to Na3PO4, pH did not change dramatically as it did with NaCl, only decreased from 9.30 pH to 8.73 pH. Comparing the pH changes of water and NaCl, the results seems that both have dramatic decrease in the pH level. The results shows that NaCl acted more as a water because when HCl was added, the pH dropped from

The purpose of this lab was to find that what chemical change has taken place, identify the type of reaction based on the reactants and products of a reaction, and describe reactions by writing word equations and balanced chemical equations.

To understand this lab there is knowledge prior to the lab that was taught. A physical change is a change affecting the form of a chemical substance but not its chemical composition. Physical changes can be used to separate mixtures into their component compounds. An example of a physical change is a popsicle freezing in the freezer. A chemical change is any change that results in a new formation of chemical substances. An example of a chemical change is when rust forms on nail. The signs to look for to see if there is a chemical change are color change, odor change, production of bubbles and gas, production of heat and light, and production of a precipitate. If any of these signs happen in the lab it is a chemical change. The question for

During the experiment, the solution was agitated at 350rpm for two flow rates, 80 mL/min and 100 mL/min . As seen in Figure 1, the 100mL/min flow rate solution dropped in pH faster than the solution with a 80 mL/min flow rate. This was due to the solution not being saturated at 80mL/min and able to conduct a chemical reaction. Another important observation was that due to the lack of data, some of the trends had to be predicted for both flow rates. This can be observed in Figure 2 and Figure 3. Subsequently, it was predicted that the higher flow rate would have had a steeper slope.