Chemistry Project to To Determine which Antacid Neutralizes Stomach Acid Most

To Determine which Antacid could Neutralize the most Stomach Acid.

.: AIM :. To Determine which Antacid could Neutralize the most Stomach Acid.

INDEXo Objectiveo Introductiono Acidso Stomach Acido Some foods containing acids

o DRUG NAMES                                                o SOME COMMONLY USED ANTACIDS      ALUMINIUM HYDROXIDE                        MAGNESIUM HYDROXIDE                      CALCIUM CARBONATE                       o Action mechanismo Indicationo Side Effects

Problems with reduced stomach acidity Experiment Design Material Required Procedure Observation And Calculation Result Precautions Bibliography

OBJECTIVE

The purpose of this experiment was to determine which antacid could neutralize the most stomach acid.

I became interested in this idea when I saw some experiments on medicines and wanted to find out some scientific facts about medicines.

The information gained from this experiment will help people know which antacid they should look for in the stores. It will also let them know which antacid will give them the most comfort. This could also save consumers money and provide better health.

INTRODUCTION

Digestion in the stomach results from the action of gastric fluid, which includes secretions of digestive enzymes, mucous, and hydrochloric acid. The acidic environment of the stomach makes it possible for inactive forms of digestive enzymes to be converted into active forms (i.e. pepsinogen into pepsin), and acid is also needed to dissolve minerals and kill bacteria that may enter the stomach along with food. However, excessive acid production (hyperacidity) results in the unpleasant symptoms of heartburn and may contribute to ulcer formation in the stomach lining. Antacids are weak bases (most commonly bicarbonates, hydroxides, and carbonates) that neutralize excess stomach acid and thus alleviate symptoms of heartburn. The general neutralization reaction is:

Antacid (weak base) + HCl (stomach acid) —> salts + H20 + C02

The hydrochloric acid solution used in this experiment (0.1 M) approximates the acid conditions of the human stomach, which is typically 0.4 to 0.5% HQ by mass (pH ~ 1).Antacids help people who have or get heartburn. The following information will help people understand how stomach acid works and what antacid will help those most.ACIDS

Acids are a group of chemicals, usually in liquid form. They can be recognized by their sour taste and their ability to react with other substances. Acids are confirmed as an acid by their pH. The pH of acids ranges from 0-6.9 (below 7). The two main acids are: mineral acid and organic acid. The three well known acids that are sulphuric acid (H2S04), nitric acid (HN03), and hydrochloric acid (HCl).

STOMACH ACID

Stomach acid is very dangerous. If a person was to have an ulcer and the stomach acid was to escape it would irritate their other organs. Stomach acid is highly acidic and has a pH of 1.6. Stomach acid is hydrochloric acid produced by the stomach. If there is too much stomach acid it can cause heartburn. Heartburn is when stomach acid is produced in abnormal amounts or location. One of the symptoms of heartburn is a burning feeling in the chest or abdomen.

SOME FOODS CONTAINING ACIDS

Almost all foods and drinks and even medicines have ingredients that are different acids. Here are some examples: Aspirin (acetylsalicylic acid), Orangejuice (ascorbic acid/Vitamin C), Sour Milk (lactic acid), Soda Water (carbonic acid), Vinegar (acetic acid), Apples (malic acid), and Spinach (oxalic acid).

ANTACID

An antacid is any substance that can neutralize an acid. All antacids are bases. A base is any substance that can neutralize an acid. The pH of a base is 7.1-14(above 7). All antacids have chemical in them called a buffer. When an antacid is mixed with an acid the buffer tries to even

out the acidity and that is how stomach acid gets neutralized. In an antacid it is not the name brand that tells how well it works it is something called an active ingredient. Not all antacids have a different active ingredient. Some have one of the same active ingredients and some have all of the same active ingredients. Almost all the antacids that have the same active ingredient work the same amount as the other. The active ingredient of most of the antacids is bases of calcium, magnesium, aluminium.

SOME FAMOUS ANTACID BRANDS

1. Alka-Seltzer – NaHCO3 and/or KHCO3

2. Equate – Al(OH)3 and Mg(OH)2

3. Gaviscon – Al(OH)3

4. Maalox (liquid) – Al(OH)3 and Mg(OH)2

5. Maalox (tablet) – CaCO3

6. Milk of Magnesia – Mg(OH)2

7. Pepto-Bismol – HOC6H4COO8. Pepto-Bismol Children’s – CaCO3

9. Rolaids – CaCO3 and Mg(OH)2

10. Tums – CaCO3

11. Mylanta

SOME IMPORTANT COMMONLY USED ANTACIDS

1.ALUMINIUM HYDROXIDE

Aluminium hydroxide, Al(OH)3, Alum, is the most stable form of aluminium in normal conditions. It is found in nature as the mineral gibbsite (also known as hydrargillite) and its three, much more rare, polymorphs: bayerite, doyleite and nordstrandite. Closely related are aluminium oxide hydroxide, AlO(OH), and aluminium oxide, Al2O3, differing only by loss of water. These compounds together are the major components of the aluminium ore bauxite. Freshly precipitated aluminium hydroxide forms gels, which is the basis for application of aluminium salts as flocculants in water purification. This gel crystallizes with time. Aluminium hydroxide gels can be dehydrated (e.g., with the utility of water-miscible non-aqueous solvents like ethanol) to form an amorphous aluminium hydroxide powder, which is readily soluble in acids.

USE AS A FIRE RETARDANT

Aluminium hydroxide also finds use as a fire retardant filler for polymer applications in a similar way to magnesium hydroxide and hydromagnesite. It decomposes at about 180 °C giving off water vapour.

2.MAGNESIUM HYDROXIDE

magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. As a suspension in water, it is often called milk of magnesia because of its milk-like appearance. The solid mineral form of magnesium hydroxide is known as brucite.

Magnesium hydroxide is common component of antacids and laxatives; it interferes with the absorption of folic acid and iron.  Magnesium hydroxide has low solubility in water, with a Ksp of 1.5×10−11; all of magnesium hydroxide that does dissolve does dissociate. Since the dissociation of this small amount of dissolved magnesium hydroxide is complete, magnesium hydroxide is consi dered a strong base.

Mg2+ (aq.) + 2 OH− (aq.) → Mg(OH)2 (s)

USES

Milk of magnesia is sold for medical use as chewable tablets, capsules, and as liquids having various added flavors. It is used as an antacid, though more modern formulations combine the antimotility effects of equal concentrations of aluminum hydroxide to avoid unwanted laxative effects.

Magnesium hydroxide powder is used industrially as a non-hazardous alkali to neutralise acidic wastewaters. It also takes part in the Biorock method of building artificial reefs.

Solid magnesium hydroxide has also smoke suppressing and fire retarding properties. This is due to the endothermic decomposition it undergoes at 332 °C (630 °F) :

Mg(OH)2 → MgO + H2O

Calcium carbonate is a chemical compound with the chemical formula CaCO3. It is a common substance found in rock in all parts of the world, and is the main component of shells of marine organisms, snails, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime, and is usually the principal cause of hard water. It is commonly used medicinally as a calcium supplement or as an antacid, but excessive consumption can be hazardous.

CHEMICAL PROPERTIES

Calcium carbonate shares the typical properties of other carbonates. Notably:

it reacts with strong acids, releasing carbon dioxide:

CaCO3(s) + 2 HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)

it releases carbon dioxide on heating (to above 840 °C in the case of CaCO3), to form calcium oxide, commonly called quicklime, with reaction enthalpy 178 kJ / mole:

CaCO3 → CaO + CO2

Calcium carbonate will react with water that is saturated with carbon dioxide to form the soluble calcium bicarbonate.

CaCO3 + CO2 + H2O → Ca(HCO3)2

This reaction is important in the erosion of carbonate rocks, forming caverns, and leads to hard water in many regions.

USES

The main use of calcium carbonate is in the construction industry, either as a building material in its own right (e.g. marble) or limestone aggregate for roadbuilding or as an ingredient of cement or as the starting material for the preparation of builder’s lime by burning in a kiln.

Calcium carbonate is also used in the purification of iron from iron ore in a blast furnace. Calcium carbonate is calcined in situ to give calcium oxide, which forms a slag with various impurities present, and separates from the purified iron.

Calcium carbonate is widely used as an extender in paints, in particular matte emulsion paint where typically 30% by weight of the paint is either chalk or marble.

ACTION MECHANISM

Antacids perform neutralization reaction, i.e. they buffer gastric acid, raising the pH to reduce acidity in the stomach. When gastric hydrochloric acid reaches the nerves in the gastrointestinal mucosa, they signal pain to the central nervous system. This happens when these nerves are exposed, as in peptic ulcers. The gastric acid may also reach ulcers in the esophagus or the duodenum.

Other mechanisms may contribute, such as the effect of aluminium ions inhibiting smooth muscle cell contraction and delaying gastric emptying.

Antacids are commonly used to help neutralize stomach acid. Antacids are bases with a pH above 7.0 that chemically react with acids to neutralize them. The action of antacids is based on the fact that a base reacts with acid to form salt and water.

INDICATIONS

Antacids are taken by mouth to relieve heartburn, the major symptom of gastro esophageal reflux disease, or acid indigestion. Treatment with antacids alone is symptotic and only justified for minor symptoms. Peptic ulcers may require H2- receptor antagonists or proton pump inhibitors.

The usefulness of many combinations of antacids is not clear, although the combination of magnesium and aluminium salts may prevent alteration of bowel habits.

SIDE EFFECTS

Aluminium hydroxide: may lead to the formation of insoluble aluminium phosphate complexes, with a risk for hypophosphate and osteomalacia. Although aluminium has a low gastrointestinal absorption, accumulation may occur in the presence of renal insufficiency. Aluminium containing drugs may cause constipation.

Magnesium hydroxide: has a laxative property. Magnesium may accumulate in patients with renal failure leading to hypo magnesia, with cardiovascular and neurological complications.

Calcium: compounds containing calcium may increase calcium output in the urine, which might be associated to renal stones. Calcium salts may cause constipation.

Carbonate: regular high doses may cause alkalosis, which in turn may result in altered excretion of other drugs, and kidney stones.

PROBLEMS WITH REDUCED STOMACH ACIDITY

Reduced stomach acidity may result in an impaired ability to digest and absorb certain nutrients, such as iron and the B vitamins. Since the low pH of the stomach normally kills ingested bacteria, antacids increase the vulnerability to infection. It could also result in the reduced bioavailability of some drugs. For example, the bioavailability of ketocanazole (antifungal), is reduced at high intragastric pH (low acid content).

EXPERIMENT DESIGN

The constants in this study were:

-   Type of acid

-  Consistency of procedures

The variables in the study were:

-Different types of antacid used The responding variable was:

-  The amount of stomach acid each antacid could neutralize measured in ml.. MATERIAL REQUIRED

Burette, pipette, titration flask, measuring flask, beaker, weighing machine, concentrated sulphuric acid, methyl orange, antacid samples.

PROCEDURE

Prepare half litre of N/10 HCl solution by diluting 10 ml of the concentrated acid to 1 litre.

Prepare N/10 sodium carbonate solution by weighing exactly 1.325 g of anhydrous sodium carbonate and then dissolving it in water to prepare exactly 0.25 litre of solution.

Standardize the HCl solution by titrating it against the standard sodium carbonate solution using methyl orange as indicator.

Take 20 ml of standardized HCl in the conical flask, use methyl orange as indicator and see the amount of base used for neutralization.

Powder the various sample of antacids tablets and weigh 10 mg of each. o Take 20 ml of standardized HCl solution in the conical flask; add the weighed

samples to it.o Add two drops of methyl orange and warm the flask till most of the powder

dissolves. Filter off the insoluble material.o Titrate the solution against the standardized Na2C03 solution till a permanent red

tinge appears.o Note the amount of base used for titration and note the reduction in the amount of

base used.

S.No. Intial burettereading

Final burettereading

Volume of acidUsed(in ml)

1 0.0ml 15ml 15.02 0.0ml 14ml 14.03 0.0ml 15ml 15.0

o Repeat the experiment with different antacids.

OBSERVATIONS AND CALCULATIONS 1. Standardization of HCl solution

Volume of N/10 sodium carbonate solution taken—20.0 ml

Concordant reading—15.0 ml Applying normality equation

N1V1(acid) — N2V2(base)

N (15) — (1/10) 20

Normality of HCl solution, N1 — 0.133 N

2. Neutralization of standardized HCl solution used

3. Analysis of antacid tablets

S.No. Antacid Initial reading of burette

Final reading of burette

Volume of Na2C03

1 Gelusil 0.0 ml 15.0 ml 15 ml2 Aciloc 150 0.0 ml 22.0 ml 22 ml3 Fantac 20 0.0 ml 25.0 ml 25 ml4 Pantop 20 0.0 ml 20.0 ml 20 ml

5 Ocid 10 0.0 ml 7.0 ml 7 ml

Weight of the antacid tablet powder— 10 mg Volume of HCl solution added— 20.0 ml

RESULT

The most effective antacid out of the taken samples is acid 10.

PRECAUTIONS

All apparatus should be clean and washed properly. Burette and pipette must be rinsed with the respective solution to be put in them. Air bubbles must be removed from the burette and jet. Last drop from the pipette should not be removed by blowing. The flask should not be rinsed with any of the solution, which are being titrated.

Bibliography

Wikipedia -the free encyclopedia Website : http:/ /www.icbse.com Foundation Chemistry-12 Comprehensive Practical Chemistry -12