Aim: To Find and test the Iron content in different food sources INTRODUCTION:
A Redox titration was used in order to perform this experiment. Reduction/oxidation (redox) process occurs when electrons are transferred from a donor species (the reducing agent) to another acceptor species (the oxidizing agent). It happens between an analyte and a titrant. A redox titration is done just as a normal titration is done, however instead of titrating an acid against a base, an oxidizing agent is titrated against a reducing agent and the equivalence point is reached when the reducing agent is completely oxidized by the oxidizing agent. (Chang, 2011). An indicator is used just as in an acid-base titration, although in this experiment because of its self-indicating property KMnO4 the titrant, it is also used as indicate when the equivalence point is reached as it is titrated with Fe2+ Iron is the most abundant metal in the Earth’s crust after Aluminum. It is found in many ores such as hematite, siderite and magnetite.Iron is a basic part of many proteins and enzymes that maintain good health. In humans, iron is a vital constituent of proteins involved in oxygen transport. It is also essential for the regulation of cell growth and differentiation. A deficiency of iron limits oxygen delivery to cells, resulting in fatigue, poor work performance, and decreased immunity. On the other hand, excess amounts of iron can result in toxicity and even death.
Almost two-thirds of iron in the body is found in haemoglobin, the protein in red blood cells that carries oxygen to tissues. Lesser amounts of iron are found in myoglobin, a protein that helps supply oxygen to muscle, and in enzymes that assist biochemical reactions. Iron is also found in proteins that store iron for future needs and that transport iron in blood. Iron stores are regulated by intestinal iron absorption. There are two forms of dietary iron: haeme and nonhaeme. Haeme iron is derived from haemoglobin, the protein in red blood cells that delivers oxygen to cells. Haeme iron is found in animal foods that originally contained haemoglobin, such as red meats, fish, and poultry. Iron in plant foods such as lentils and beans is arranged in a chemical structure called nonhaeme iron. This is the form of iron added to iron-enriched and iron-fortified foods. Haeme iron is absorbed better than nonhaeme iron, but most dietary iron is nonhaeme iron. Iron provided by dietary supplements is often found as iron (II) fumarate and elemental iron which is not easily absorbed by our bodies is often added to foods such as breakfast cereals.This experiment tests the iron contents of Iron supplement tablet, beef liver and fortified corn flakes. METHOD:
The burette was set up in a clamp and stand. A small funnel was put into the top of it and 0.005M solution of Standard Potassium magnate was poured into it, until the top graduation mark. A beaker was put the tap of the burette and liquid was run so as to fill the level of the liquid was read from the burette and recorded as the initial reading.
2cm3 of the iron tablet was ground with 1.0moldm3 of sulphuric acid. The mixture was then transferred into a 100cm3 volumetric flask and 1.omoldm3 of sulphuric acid was added to it to make it 100cm3.It was corked and shaken thoroughly .Afterwards 20.0cm3 of the prepared solution was transferred into a conical flask to be titrated.
20g of beef liver was cut into tiny pieces and crushed with 2cm3 of 1.0moldm3 of sulphuric acid. The mixture was passed through a muslin sheet to separate the solution and the solid matter .100cm3 was of the solution was then transferred into a volumetric flask and mixed with 1.0moldm3 of sulphuric acid. It was corked and shaken thoroughly .Afterwards 20.0cm3 of the prepared solution was transferred into a conical flask to be titrated. Fortified cornflakes:
Exactly 30g of the cornflakes was crushed with 2cm3 of 1.0moldm3 of sulphuric...
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