Essays on Chemical Reaction

It is clear all of the contracted workers associated with the case study all completed their orientation training. At the same time, these new employees were tasked with the job of isolating the acid feed steam for the Claus unit, which they failed to do. This paper will discuss the hazards present, the steps the incident command must conduct, explain changes to plan if polymerization occurs, and explains changes to plan based on the result of the post incident critique. First of all, it is clear continuous training is essential to the refreshment of knowledge in order to avoid ...

Everyone loves the food at the dining table to be appealing to their senses besides their taste buds through attractive colors and flavors. For instance, one cannot imagine a loaf of bread without its trademark golden brown crust. How do foods get their unique color and aroma? A series of reactions known as Maillard reactions produce countless chemical compounds that give foods like bread, chocolates, potato chips and roasted meat their unique colors (Copeland, 2016). These reactions take place at high temperatures of around 130℃ when raw food items are baked, roasted or fried. This explains why boiled, steam-cooked ...

Introduction

Reduction reactions are very important in chemistry as they are effective processes for synthesizing new compounds from existing ones. In organic chemistry, a compound is said to be reduced if it acquires new hydrogen. There are diverse reagents for carrying our reduction reactions. Two of these are sodium borohydride (NaBH4) and lithium aluminum hydride (LiAlH4) - the latter is a more powerful reducing agent compared to the former. In this experiment, NaBH4 was used to reduce p-Nitrobenzaldehyde to form p-Nitrobenzyl alcohol. NaBH4was used over LiAlH4 in this experiment, because LiAlH4 would also reduce the nitro group of the aldehyde.

Experimental:

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Literature Review

Abstract Innovations and modifications that produce cost reductions and enhance performance have driven the evolution of the classic solid rocket and the liquid bipropellant rocket into hybrid models that integrate the predominant solid and liquid model features into more sensical, more economical fabrications of design. The commercial spacecraft demands for aerospace propulsion have also evolved to include a market for environmentally sustainable hybrid rocket engines that has yet to fully mature to the Technology Readiness Level (TRL). Numerical modeling has been used as a tool to test the feasibility of new solid fuel types. ABS has been considered as ...

The question of what constitutes after life has been explored for thousands of years. Whereas it is possible to group articles clearly as living or non-living, it is tough to define some of the characteristics that constitute life. In biology, life is widely defined as the possession of several features such as respiration, feeding, and an ability to sense irritation. Growth and development, as well as the disposal of waste, are also properties of living beings, besides being able to reproduce (Kurzgesagt). Kurzgesagt video, “What is life? Is death Real,” explores some of the elements that constitute life in ...

Abstract

In this experiment, benzene was treated with hydrogen in the presence of Pt/SiO2 as an example that can be applied on industrial operations to show that the most recently modernized methods of neutron total scattering that cover a wide Q-range allow the use of appropriate catalytic chemistry that can be measured on time domain to probe directly on site the hydrogenation of benzene within the catalyst pore. Based on this method, it is possible to study the rates of reaction on length scales that can provide measurements equivalent to the size of an atom or a nanometre. Furthermore, the ...

Abstract

A dual carriageway is proposed to be constructed in the town moving in the east-west direction. The dual carriage is intended to be eight-kilometer long looping around the northern part of the town. Cut and fill techniques are used where half of the road is cut to a maximum of six meters. Half of the road is supported by an embankment of six meters high. At the eastern and western ends of the road are of grade where the road joins other roads and at the middle where the cut sections meet the filled sections. The road has a ...

Surgical Anesthesia

Pharmacology and Indications Licocaine Licocaine is a type of medication used with an aim of numbing tissues and nerves within a given area of the body, which provides that anesthetic effect for the body. The most popular brand names for this particular drug are xylocaine and lignocaine. Some of the common effects associated with this particular medication include drowsiness, muscle twitching, nausea, and confusion (1). The severity of the side effects depends wholly on a patient’s reaction to the chemical composition of the drug. Regarding its mode of action, licocaine works by blocking the voltage-gated Na+ channels, which ...

Introduction

There are environmental chemical processes which require light to react. These processes are called photochemical reactions. Photochemical reaction is commonly initiated due to the absorption of solar energy or light. When molecules absorb energy in the form of light, the atoms are converted in a transient excited state (Larson & Weber, 1994). This transition state or excited has completely different physical and chemical properties with the initial state of the molecule. The excited states also have more tendencies to react since they are considered stronger acids and stronger reductants that the initial state of the molecule. The excited state of ...

Chemical Weathering

Chemical weathering in the mid-latitudes is the process where rocks are weakened and disintegrated by chemical reactions that occur in the soil. Some of the chemical reactions that cause chemical weathering are oxidation, carbonation, and hydrolysis. These processes are involved in either forming or destroying minerals and therefore altering the nature of the mineral composition of the rocks. The process of chemical weathering on rocks characterizes the second stage of rock disintegration. The first process occurs during physical weathering and it involves disintegrating rocks into small pieces which are further broken into smaller pieces by chemical weathering. The most ...

Stratospheric Ozone Depletion

Ozone depletion is a natural phenomenon of the earth’s stratosphere due to the presence of free radicals that are from natural causes such as volcanic activity. However, as man evolved, he discovered his environment and built industries during the industrial revolution. These industries emitted tones of pollutants into the atmosphere, including compounds Ozone Depleting Substances. The continuous use of CFCs also contributes to the effect significantly. The worst case of ozone depletion ever recorded happened in 2006, during winter and early spring in Antarctica. That sounded a loud alarm to environmental scientists, political leaders and civil organizations come ...

Introduction

The European Union is one of the most united bodies in the world today. EU epitomizes unity and centres in the common good of its members. Obviously, the business interrelation and other working domains of the Union has gone a long way to garner success for its members. As a united body, the EU represents the most powerful force in the world that cannot be thwarted by external powers. Although this union can be labelled a success by all and sundry but it fails in some aspects especially in issues relating to the environment but not in toto. This ...

An explosion at a fertilizer manufacturing plant in the Western part of Texas that occurred in early 2013 killed 15 people and injured 180 more. The explosion leveled buildings within a five block radius and the instruments at the Geological Survey of the United States recorded a 2.1 magnitude earthquake. The explosion was caused by the reagents used as raw materials for fertilizer manufacturing. Inorganic fertilizer is manufactured from chemical substances such as ammonium nitrate and anhydrous ammonia, which had been stocked at the West plant during the explosion. This paper explores the cause of the explosion, the chemical ...

Abstract page

One of the most important assets of the industrial application these days is the Fluidized bed reactors. When gasses, solids, and liquids contact simultaneously, a large number of industrial process reactions are involved. All these operations need a multiphase reactor to be carried out. Since a variety of multiphase chemical reactions can be carried out in a Fluidized Bed Reactor, it is interesting to learn about its functioning, various types, application, advantages, and disadvantages. Initially, fluidized bed reactors were built for the petrochemical and oil industries. Now, they are widely used for producing Gasoline and other fuels, plastics, polymers, ...

How is Plant Growth Affected by Sunlight?

Introduction Background information Sunlight is essential to plants. Plants in dark room tend to grow towards sunlight. When they lack sunlight, photosynthesis does not take place causing them to wither and die. Photosynthesis takes place in the leaves of a plant. In plant leaves, there are organelles called chloroplast. They form site for photosynthesis process. They are very many in a leaf.

Within chloroplast, there is chlorophyll, that are usually green in color, hence the green coloration in plants.

Plants require air, water and sunlight for photosynthesis to occur. Air goes inside the leaf via stomata, water is absorbed from the ground through the roots and sunlight is absorbed by the chloroplasts in the leaves. Chemical ...

Introduction

The paper presents the literature review on everyday chemistry and covers the following areas: Food molecules. Chemistry using kitchen chemicals. Food safety from rotten products. The paper used Google Scholar, WorldCat, Science Direct for literature search, and the key words were: food molecules, food chemistry, kitchen chemicals, food safety and rotten.

Types of Food Molecules

Every individual knows that food contains proteins, lipids and carbohydrates. These substances are the main nutrients and are responsible for energy supply for the body. There are numerous types, some are more complicated, some are simple; some are found in nature, and some are fully artificial. However, they ...

Discussion 1: Public Speaking

I definitely agree with the statement: Knowing the background, interests, and expectations of your audience significantly increases the effectiveness of your speech. All this information will help to find the right approach, to make the speech interesting exactly for these people. It is important to use the references, which will be familiar to audience. Sometimes it might be a good idea to use jokes to lighten up the atmosphere. But if the audience doesn’t appreciate your sense of humor or they will be somehow offended by it then it will just make the matters worse. You should absolutely ...

Biology Assignment

- Cellular respiration is the metabolic process through which glucose is broken down in the cells to produce energy in the form of ATP. Anaerobic respiration or glycolysis is the anaerobic breakdown of glucose into ATP, which requires no oxygen. This process involves removal of hydrogen and electrons from glucose to generate NADH, pyruvate and energy equivalent to two molecules of ATP. In the absence of oxygen pyruvate undergoes fermentation, whereas in the presence of oxygen, pyruvate is siphoned into the mitochondria and is completely broken down. The citric acid cycle occurs in the matrix of the mitochondria and ...

- Describe two features that make all enzymes catalysts.

Enzymes are catalysts that increase the rate of reaction between substances and remain unchanged in the reaction. Enzymes are vital to several bodily functions and make possible such processes like metabolism and catabolism. Two features that make enzymes catalysts is their ability to lower the activation energy and their inherent tendency to combine with coenzymes and cofactors. Activation energy is the minimum energy required to activate the molecules of reactants in order to initiate a chemical reaction. Some substrates have high activation energies that would need very high temperatures to activate ...

Introduction

Coordination complex usually consists of a metallic coordination center and can be surrounded by bound molecules. Thus these are known these coordination complexes are known as ligands as they bind several molecules strongly almost irreversibly. Coordination complexes therefore coordinate covalent bonds on the molecule. There is specific nomenclature for coordination complexes. Particularly, the donor atom is the ligand that is bonded to the central atom. Here we are making Aluminium acetylacetonate, Al(acac)3, also referred to as Al(acac)3, and the metal ion is the aluminum and the donor atoms are the acetylacetonate. If there are more ...

Background

Early scientists and nutritionists believed that the most vital nutrient in living organisms, for building and maintaining the body was the protein. The role of proteins as enzymes came into existence several years later. This was around 1926 when experiments showed that enzymes were proteins. Insulin was the first protein to be sequenced. Hemoglobin was the first structure of proteins to be resolved. Myoglobin was then resolved later.

X-ray diffraction analysis (X-ray crystallography) led to the determination of the structure of the proteins (three-dimensional structure). The purification of proteins can be made possible from cellular compounds. Several methods have ...

Introduction

In a chemical reaction, either the products or reactants tend to have a higher enthalpy than the other. In some cases, the enthalpy of reactants is greater than the enthalpy of products. On the other hand, in other cases, the enthalpy of products tends to be greater than the enthalpy of reactants. A reaction involving the products with higher enthalpy than the reactants is said to be endothermic (Brown, et al, 172). On the other hand, chemical reactions where the enthalpy of reactants is higher than the enthalpy of products are said to be exothermic (Brown, et al, 172). The reaction ...

Certain elements involved in the geochemical and biogeochemical cycling are of great concern due to their limited availability both naturally or through industrial manufacture of the compounds involved in the cycles. Some of the processes involved are chemical reactions with other elements or substances. Some of these reactions are irreversible chemical reactions. This implies once the reaction has taken place, the elements are removed from natural cycle and they cannot be replaced again. As such, the more the cases of irreversible reactions, the greater the rate of reduction of these elements from the environment. Ultimately, there could be less ...

Vitamin C Clock Reaction: Kinetics

Vitamin C Clock Reaction: Kinetics

Abstract

Collision theory refers to a theory that was proposed by Max Trautz and William Lewis independently. The theory qualitatively offers an explanation on the way chemical reactions take place and the reason behind differences in reaction rates in different reactions. The rate equation for a given chemical reaction refers to the equation that provides a link between the pressure or concentrations of the reactants and the parameters that are constant partial reaction orders and the rate coefficients. This experiment aimed to determine the rate of reaction of reaction between iodide and hydrogen peroxide and determine the order ...

Abstract

Enzymes are the large biological molecules that play the role of metabolic processes responsible for maintaining the human life. They have the ability of high selectivity, as natural catalysts. They accelerate both the specifity and rate of metabolic processes, from food digestion and DNA synthesis. Most scientific enzymes are proteins in nature, even though some RNA molecules which are catalytic have been studied. The structures of enzymes normally adopt a three dimensional structure, and in order to assists in catalysis, it may employ the organic and inorganic forms. This experiment is meant to describe the properties and characteristics of enzymes ...

Part A

How Enzymes Act As Protein Catalysts in Biochemical Processes Catalysis refers to the speeding up of a chemical reaction by a catalyst. A catalyst is a substance that accelerates a chemical reaction but does not undergo a permanent chemical change in the process. Enzymes are catalysts whose building blocks are amino acids: they are proteins. Enzymes also exhibit a defined three-dimensional structure. In addition, they have a cleft on their surface called active site. The active site is the region where substrate interactions take place. Enzymes play important roles in fructose metabolism. The first step of fructose metabolism in the liver is the phosphorylation of ...

Introduction

Q1 . The fundamental requirement for a living cell to sustain itself are a carbon source, an energy source, an electron donor, an electron acceptor and elemental nutrients(N,P, S, Mg,) etc. Explain how each of these fundamental requirements are needed by the living cell to function. Explain how the cell can maintain its own internal biological processes without being in equilibrium with the external environment. The living cells can function within a constricted range of such conditions such as nutrient availability, pH, ion, temperature, etc. The cell must coordinate different chemical reactions and consolidate many different molecules into definite structures, ...

Stars begin their lives from molecular clouds or nebula of gases and dust. These gases and dusts exert forces to each other that make them want to move farther away from each other while at the same time there is gravity that attracts them together into a small space within the nebula. The chemistry which starts the star’s life begins when gravity starts winning in the war between the two aforementioned opposing forces. As gravity pulls the dust and clouds together it begins to accumulate mass and a swirling motion typical to a spinning disc. At its center are dusts (NH3, ...

Abstract

The fugacity is a term that has Latin origins, referring to pace and speed. Early work somewhere in the 20th century, on fugacity, demonstrated that chemical equilibrium is established by the free energies of reacting material. Since then, various approaches and concepts on fugacity have been provided. The gas fugacity of noble gasses has been studied, and models have been proposed for calculating the solubility of noble gasses. The development of various models has considered pressure effects, differential equilibrium between components and temperature changes. The paper discusses the evolution of various multimedia fugacity models and the fugacity of pure ...

A chemical reaction occurred between Calcium carbide (CaC2) water (H20). The reaction occurs because a cloudy (turbid) can be observed when the pieces of carbide are added to the flask containing water. Bubbling can also be observed as the reaction releases acetylene gas. The whitish or cloudy substance formed during the reaction is calcium hydroxide. A reaction between the reactants, calcium carbide (CaC2) and water. Reactants are the substances which when combined exchange chemical their ions and form other substances. The reaction involves the active ions of the dicarbide (C22-) and the Calcium (Ca2+) with the hydrogen (H+) and ...

Mechanical Engineering is a branch in the field of science that encompasses a large field of designing and manufacturing small individual parts and devices, as well as large systems. The branch is at the heart of moving products from ideas to the marketplace. The branch of engineering involves creating products that will withstand different forces and the thermal environment to ensure they function properly. It entails the design, manufacturing, analysis and maintenance of mechanical systems using principles of materials science and physics. Mechanical engineering is not only concerned about functionality of products but also about aesthetics too. In its broad application ...

Introduction 3

Definition and background 3 Structure and properties of Artemisinin 4 Structure 4 Properties of Artemisinin 5 Synthesis of artemisinin 5 Activation of artemisinin 7 Mechanism of Artemisinin action in the body 8 Side effect 10 Conclusion 10

References 13

- Table of Figures Figure 1: Structure of Artemisinin2 4 Figure 2: A synthetic strategy of chemical synthesis from cyclohexenone. 7,9,10 6 Figure 3: Reductive scission model: Homolytic mechanisms of bioactivation of the endoperoxide bridge of artemisinin and derivatives 8 Figure 4: Proposed mechanism for artemisinin mediated lipid ...

Abstract

The purpose of this experiment was to characterize aldehydes and ketones using Tollen’s test and Iodoform test. It also aims to identify an unknown substance as well as determine whether glucose is an aldehyde or a ketone using the same tests. In order to achive these purposes, four test tubes where prepared for each type of test. For Tollen’s test, each of the tubes contained 1 drop of the analyte to which 1mL of the Tollen’s reagent was added. For the Idoform test, 4 drops of each substance was used, to which 2 mL of sodium hydroxide ( ...

Chapter review

Chapter review Matter is anything that has mass and occupy space. The smallest particle of matter is referred to as an atom. An atom is the basic substance of the matter. An atom consists of; tiny subatomic substance. These substances are; proton, electron, and neutron. The protons are positively charged; electrons are negatively charged, and neutrons have no charge. The atom is divided into two parts, the center that consists of the neutrons and proton and the outer part which consist of the electrons. An atom has different properties; a physical property can be seen and observed without ...

Interactions with hazardous materials

Chemical reactions or interactions are key to the production of various useful chemical products including polymers, fuels, paints, adhesives etc. When the reactants, catalysts, mechanism of reaction, reactor operation, temperature, pressure and other parameters are known, as well as kept under control, the products or outcome are as expected. On the other hand when chemical interactions are unexpected and lead to unknown products, consequences could be disastrous leading to severe loss. Such hazardous material interactions are more common in chemical manufacture, processing, refining and storage facilities. Reactive hazards are a serious concern since the magnitude of loss could be ...

- Pressure= 1000 x (0.5)5.6/5.6 Pressure=500 mb Pressure=1000 x (0.5)8.85/5.6 Pressure=334.40 mb Pressure=1000 x (0.5)11.2/5.6 Pressure=250 mb Pressure= 1000 x (0.5)50/5.6 Pressure=2.05 mb - The temperature of the upper stratosphere is greater than that of the lower stratosphere due to the presence of the ozone layer. It is here where ozone absorbs ultraviolet light, which triggers chemical reactions. These chemical reactions produce heat, a process which is not found in the lower stratosphere. - Conduction is the transfer of heat through solid objects such as metal and ...

THE SCOPES TRIAL

The scopes trial is also famously known as the scopes monkey trial and was a trial which involved the state of Tennessee against John Thomas Scopes. The charge against scopes was teaching evolution. Apparently back in 1925 it was illegal to teach anything about evolution in schools that were funded by the state. Back then people believed in the divinity of the bible. Anything in the bible was considered truth that was incontestable by any human being irrespective of the evidence at hand. Teaching evolution was tantamount to blasphemy against morally accepted truths by the people. The Buttler act made ...

The Structure and Chemistry of a Dry Cell

A dry cell is usually referred to as a zinc-carbon cell because its components. Its electrochemical system constitutes a manganese dioxide cathode and a zinc anode. Additionally, the electrolyte is made up of zinc chloride which is solved in water and combined with ammonium chloride. For the most or commonly used batteries such as the round cells, a rod of carbon is used which is placed centrally down. The carbon rod serves as a collector of current for the positive terminal located at the top of the cell even though it is chemically inert. Current inside the dry zinc carbon cell moves through the ...

Abstract

Enzymes are biological catalysts and work by speeding up the rate of chemical reactions. The factors that affect enzyme activity include enzyme concentration, temperature, pH, and the substrate concentration. This experiment aimed to determine the effect of lemon juice, which is acidic on the activity of catechol oxidase enzyme. According to the results, high acidity inactivates the catechol oxidase enzyme. The optimum pH level for catechol oxidase enzyme can, therefore, be said to be pH 6.

Introduction

Enzymes are biological catalysts and work by speeding up the rate of chemical reactions. The enzymes achieve this by reducing the amount of ...

In the healthcare perspective, according to Gennaro et al. (2000), biochemical reactions are the chemical reactions involved in biochemical and cellular processes and particular actions of substances that affect these processes. Understanding biochemical reactions lead to the “understanding of the molecular bases of diseases”. The knowledge of receptor sites and metabolism (among other things) direct healthcare measures in efficient therapy management. Knowing normal cellular communication and metabolic pattern chemical reactions determine conditions that are abnormal in disease states. To Giese (2013), the scope of pharmaceutical reactions involve those of pharmaceutical biomolecules and biomolecule analogues and the chemical reactions involving ...

Physical property of a substance is that property which can only be observed but cannot be changed. They include color, volume and weight. On the other hand, a chemical property is that property of a substance which can only be observed through changing the chemical composition of the substance.

Difference between physical and chemical reactions

A physical reaction does not evolve a new matter. A chemical reaction on the other hand produces a new substance.

How different an element is from a compound

An element is a pure chemical material composed of the same type of atom. A compound on the other hand is entailed of atoms of unlike elements that are chemically combined together. Elements in the ...

Introduction

The cardiovascular system consists of arteries, capillaries veins blood vessels and the heart. The heart delivers nutrients and oxygen to the tissues and caries waste products for elimination from the tissues (Hester & Lusha, 2012). The regulation of the cardiovascular system occurs through a complex interaction of both neural and non-neural mechanisms that aim at guaranteeing a constant internal environment (homeostasis) in organisms (Malliani 2000). The regulation of the cardiovascular system occurs through hemodynamics, through auto regulation, hormonal regulation and neural control (Khurana, 2008). The most important of the regulatory mechanisms are closed loop reflexes like baro- reflexes, chemo reflexes and ...

Introduction

Biochemistry is the study of composition, structure and the chemical reactions taking place in living organisms. Dental biochemistry is the study of the composition, structure and chemical reactions taking place in teeth (Chary & Sharma 2004). The teeth form the sensitive part of the human being. The teeth enhance the looks of a human being and it is also for eating. When the dental formula of a human being is correct, the confidence to talk improves unlike when the dental formula is not proper. When care is not taken, the teeth will contact diseases. There are various causes of the diseases in ...

Abstract

Amylase from Bacillus Subtilis and Aspergillus oryzae were studied as representative candidates for bacterial and fungal enzymes, respectively. The activities of these two enzymes were studies comparatively over a period of 10 minutes and at temperatures of 0, 40, 60 and 95°C. The experiment was conducted to find the most effective temperatures for bacterial amylase and fungal amylase to catalyze starch hydrolysis. The data suggest that fungal enzyme was relatively more active, particularly in the first 6 minutes, than the bacterial counterpart at 0°C. On the other hand, the fungal enzyme activity deteriorated more rapidly than that ...

This article describes a study in which intrinsic motivation in students in regards to reading comprehension is studied. The study tested the idea that through presenting the students with situational interest, they would be able to create intrinsic motivation in the students, and therefore this would increase the students reading comprehension. For example, a student would do a simple lab experiment about chemical reactions and interest would be generated on this topic. The student would then read about the same types of chemical reactions. This student would then be able to form connections between the situation and the reading, and would gain ...

Muscular dystrophy is an inherited disease where the different genes that control muscular function are defective (Emery, 2008). It has been found that many forms of dystrophy are caused by a deficiency in dystrophin, which is a muscle protein (Emery, 2008). This disease is not infectious and cannot be acquired from any activity. It is characterized by muscle weakness and wasting where the specific muscles affected vary for different types of dystrophy (Emery, 2008).

Among the various types of muscular dystrophy, the Duchenne muscular dystrophy is the most prevalent, with an occurrence of twenty to thirty cases for every one ...

Enzymes are sometimes referred to as biochemistry workhorses because they are utilized by many scientists to speed up a number of chemical reactions. Enzymes are proteins that speed up, or in other words catalyze, specific biological and chemical reactions by increasing the rates of reaction by more than a million factors. An example of these enzymes is Pectinase, which is the enzyme that catalyzes pectin breakdown. Pectin is a part of the cell wall of fruits like tomatoes, mangoes, oranges and apples. Pectins are large colloidal molecules and they are responsible for holding or determining the amount of dispersed particles in extracted ...

Summary: Examination of a biotechnology patent Theoretically, thermal cycling refers to a process of temperature regulation scheme that is used to strengthen variety of materials or lengthen their durability. Thermal cycling apparatus and method refers to the equipment and technique used to carry out thermo cycling processes. Improved thermal cycling apparatus and relates to the modern advanced inventions of equipments and methods of carrying thermoregulation processes and minimizing related movement of fluids from two zones with two different temperatures to control chemical reactions. Background of the invention Temperature is one of the main factors that have been found ...

Abstract

Lemons have a lot of electrolytes, in form of citric acid. This acid assists in breaking down the atomic configuration of the copper and zinc plates that is placed in the lemon during such an experiment. Once the copper and zinc has been broken down, electrons are liberated. The copper and zinc then become electrodes. Electrodes permit the electrons to flow liberally through them. These free electrons habitually flow from negative electrode to positive one. In this experiment the copper is the positive electrode and the zinc is the negative. The movement of these electrons are computed in the lighting ...