Acids and bases in aqueous solutions will conduct electricity because they contain dissolved ions. Therefore, acids and bases are electrolytes. Strong acids and bases will be strong electrolytes. Weak acids and bases will be weak electrolytes. In , the Swedish chemist Svante Arrhenius proposed two specific classifications of compounds, termed acids and bases.
When dissolved in an aqueous solution, certain ions were released into the solution. Chemically, you can recognize an acid because it is made up of hydrogen H ions which come first in its chemical formula e. Acids have the following properties, which we will explore in more detail throughout this activity. Acids taste sour, have a pH definition: a scale measuring how acidic a substance is less than 7 and react with bases and carbonates.
Bases can be recognized when the chemical formula ends with a hydroxide OH ion or a carbonate CO 3 ion. Bases are also referred to as alkaline.
Bases are less common in the food we eat, but are still present as ingredients like baking soda and baking powder. Bases taste bitter, have a pH greater than 7 and react with acids. The pH scale is a scale used to classify how acidic or alkaline a substance is. As you move left on the pH scale, a substance is more acidic. As you move right on the pH scale, a substance is less acidic and more alkaline, or basic. The pH scale is logarithmic, meaning that every change of one on the pH scale means the acidity changes by ten times.
For example, a substance with a pH of 4 is ten times more acidic than a pH of 5. A substance of pH 3 is ten times more acidic than a pH of 4, but is one hundred times more acidic than a pH of 5. You can tell the pH of a substance by using indicators, such as red and blue litmus paper or universal indicator. Universal indicator is first dipped into the substance being tested.
Then the colour is matched to a provided scale, as shown in the image below. For example, the substance tested below is pH 2, since the colour on universal indicator matches the colour swatch below 2.
Universal indicator can be either coloured strips of paper or in liquid form. Watch this video showing the use of universal indicator to test the pH of a variety of bottled water brands. You can do this online at www. The Yellow Card Scheme is used to make pharmacists, doctors and nurses aware of any new side-effects that medicines or any other healthcare products may have caused.
If you wish to report a side-effect, you will need to provide basic information about:. You should consult your doctor if your symptoms worsen, or if you experience any of the following problems which can indicate a serious gut disorder:. Gastro-oesophageal reflux disease and dyspepsia in adults: investigation and management ; NICE Clinical Guideline Sept - last updated October Br J Gen Pract.
I have also recently developed Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Egton Medical Information Systems Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions. In this series. In this article What are antacids? How do antacid tablets work?
Can I buy antacids or do I need a prescription? When is the best time to take antacids? How quickly do antacids work? How long is treatment needed? Who can and cannot take antacids? Antacid side-effects Other considerations. Antacids In this article What are antacids? Want to see a dietician? Book a private assessment with a qualified dietician today. Antacid preparations serve to neutralize gastric acid after it is secreted.
These still-helpful agents have a continuing role in treating mild, occasional heartburn and supplementing prescription drugs in more severe disease. They are traditional, cheap, handy, and relatively safe — although they are not without risks and side effects can occur. Heartburn is also a common symptom of GERD, or gastroesophageal reflux disease. GERD is a long-term condition. In GERD, heartburn or other symptoms are frequent and persistent. The principal approach to treatment of GERD is to reduce gastric acidity.
There are powerful drugs used to reduce the secretion of acid, which include the histamine2 H2 receptor antagonists, and the proton pump inhibitors, or PPIs.
Learn more about GERD. Antacids are the oldest effective medications for heartburn. Chalk calcium carbonate has been chewed for centuries to provide some relief and is still popular. Most commercially available antacids are combinations of aluminum and magnesium hydroxide. Some antacids are combined with an alginate [an insoluble substance that increases surface tension in liquid] to form a compound that floats on gastric fluids to protect the esophagus from acid exposure.
Antacid tablets are slow acting and have less neutralizing power than a liquid form of antacid. Tablets must be chewed, and may not interact well with gastric acid. For most, the convenience of tablets far outweighs these slight disadvantages. Note that only a few commercial preparations are cited as examples. While generally a safe household remedy, its high sodium content is a disadvantage.
Bicarbonate reacts with stomach hydrochloric acid to release carbon dioxide gas CO2 that is quickly absorbed, but sometimes elicits a satisfying belch. Those who require sodium restriction for high blood pressure or heart disease should avoid bicarbonate.
Like magnesium citrate or magnesium sulfate, it is an effective laxative. Were it not for its tendency to cause diarrhea, magnesium hydroxide would be the most ideal antacid. To counter the diarrhea effect, most manufacturers add aluminum hydroxide, which is constipating. The combination substantially raises the price, and the addition of the less-effective aluminum hydroxide reduces the antacid benefit.
Magnesium hydroxide is not absorbed by the intestine. However, its interaction with stomach acid produces magnesium chloride that can be absorbed. Magnesium has many functions in human cells, including the heart, and may have harmful effects if levels in the blood rise. This is not a problem for a person with healthy kidneys, but magnesium should be avoided if renal failure is present.
Heartburn that occurs now and then is common.
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