Chemical Reaction Lab Report

Due to this fact, the concentration of copper in the solution is able to be calculated by using light absorbance. Since zinc doesn’t absorb any light, we are able to deduce that the greater the absorbance, the greater the concentration of copper.

The objective of this lab was to use prior knowledge about the Law of Conservation of Matter and of different types of chemical reactions in order to evaluate if aluminum disappears during the reaction and copper appears. The reaction that occurred between Copper (II) Chloride and aluminum was a single replacement reaction. Clear signs that a chemical reaction took place include heat release/temperature change, color change, and formation of a precipitate. When a single element, in this instance aluminum, replaces another element in a compound, copper, a single replacement reaction occurs. A basic formula for these reactions is AB + C → AC + B.

The purpose of the experiment is to cycle solid copper through a series of five reactions. At different stages of the cycle, copper was present in different forms. First reaction involves reaction between the copper and nitric acid, and copper changed from elemental state to an aqueous. The second reaction converted the aqueous Cu2+ into the solid copper (2) hydroxide. In the third reaction Cu(OH)2 decomposed into copper 2 oxide and water when heated. When solid CuO reacted with sulfuric acid, the copper returned to solution as an ion (Cu2+). The cycle of reactions was completed with the reaction where elemental copper was regenerated by Zn and Cu

Washing of the copper is necessary in this experiment to separate the iron from the copper and make sure the iron is not counted in the mass of the copper.

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?

No vigorous reaction occurred; rather, the zinc sample disintegrated slowly and turned red in color.

Oxidation involves the gain of electrons of hydrogen or the loss of oxygen or decrease in oxidation state. If zinc completely reacts with HCL, then the theoretical yield of copper should be equivalent to the actual yield.

The understanding of oxidation and reduction must be clear to carry out this lab. With the understanding of these concepts we can calculate or hypothesize for the properties of each element or compound. Oxidation involves the gain of electrons of hydrogen or the loss of oxygen or decrease in oxidation state. If zinc completely reacts with HCL, then the theoretical yield of copper should be equivalent to the actual yield.

Zinc chloride was easier to manipulate than Copper chloride because the solid was less condensed than Copper

I started with elemental copper metal and then reactions occur step by step as follows:

PURPOSE: Ranking the metals copper, magnesium, iron, zinc and hydrogen in terms of their reactivity.

Experimental approach: In the first reaction, copper metal turnings oxidize when put in contact with nitric acid and become copper nitrate.

Copper has a very important biological and environmental significance, and is considered one of the most important elements all over the world. Within this experiment, copper’s ionic and elemental forms will be examined. This will be done by exposing copper to a series of chemicals and transforming copper into a nitrate, a hydroxide, an oxide, a sulfate, and then changing it back to its original element, copper. This process is known as the Copper Cycle, and can be used to study and observe the different types of chemical reactions that exist within our biological and environmental systems.

When one looks back at the procedure of the experiment, trials 1, 2, 3, 4, 5, and 6 all use 6 M HCl for their reactions, and if this were to be substituted for 6 M HNO3, then these reactions would have still taken place, except in trial 2 because copper is less reactive than hydrogen in all cases, but their final observations may yield different colored solids and solutions (Beran,

LEARNING OBJECTIVES The learning objectives of this experiment are to. . . ! ! determine changes in enthalpy and entropy of the reaction of zinc with copper sulfate using two methods: electrochemistry and calorimetry. compare the enthalpy values obtained by the two methods. BACKGROUND Thermodynamics is concerned with energy changes that occur in chemical and physical process es. The enthalpy and entropy changes of a system undergoing such processes are interrelated by the change in free energy, ªG, according to the equation