Pure lime, or quicklime, is calcium oxide. Its ease of manufacture and chemical properties make it an important industrial chemical.
Lime has a long history dating from the earliest of times. Its main uses were as an ingredient in mortar and as a soil fertiliser.
From the earliest of times, lime has been made by heating limestone to high temperatures. Production methods have evolved from heating limestone in open fires, to the use of brick lime kilns at the start of the 17th century, to today’s horizontal rotating kilns several metres in diameter and up to 100 metres in length. These modern kilns operate at a temperature of about 1100-1200°C, allowing rapid conversion of limestone into lime.
Lime reacts readily with water to produce slaked lime, which is the chemical compound calcium hydroxide. A considerable amount of heat energy is released during this reaction.
Calcium hydroxide is sparingly soluble in water producing an alkaline solution known as limewater. When carbon dioxide gas is passed through or over limewater, it turns milky due to the formation of calcium carbonate.
Coal and gas-fired power stations produce large volumes of gaseous product, some of which is sulfur dioxide. Lime and slaked lime are both used to reduce these sulfur emissions.
Slaked lime reacts with chlorine gas to produce the bleaching agent calcium hypochlorite – a common form of ‘swimming pool’ chlorine.
When heated with coke, a form of carbon, calcium oxide combines to form calcium carbide. When calcium carbide is mixed with water, a gas called acetylene is produced. This is the fuel of the oxy-acetylene gas torch used in the metals industries to cut and weld.
Mortar is a workable paste used to bind construction bricks and blocks together. Lime mortar is made by mixing lime, sand and water. It is one of the oldest types of mortar dating back to ancient times. Nowadays, mortar is made by mixing cement powder, sand and water.
The setting of lime mortar into a hard, binding material involves reaction with atmospheric carbon dioxide to produce calcium carbonate crystals that lock the sand grains tightly together.
Fresco is a painting technique that involves applying pigment to a fresh surface of lime mortar.
This technique was extensively used by Renaissance painters in 15th and 16th centuries – some of the works created such as Michelangelo’s painting of the Sistine Chapel ceiling are marvelled at by a continuous stream of visitors to the Vatican each year.
The chemical formula of lime or quicklime is CaO. The chemical name of lime is calcium oxide. On the other hand, the chemical formula of limewater is Ca(OH)2 and the chemical name of this substance is calcium hydroxide.
Lime – an interesting physical property
If a marble-sized piece of lime is heated to a high temperature, it emits a very bright white light. In the 1820s, British Army officer Thomas Drummond used this property of lime to develop a light that could be used in lighthouses and on the battlefield. Called Drummond lights, they eventually replaced the gas lights used in music halls and theatres. Performers and actors were now ‘in the limelight’ when on stage.
Rare-earth metal oxides (cerium and thorium oxides) also show this property.
pH of Lemon Juice: Is lemon juice acidic or alkaline?
FAQ
What chemical is lime juice?
What is the formula for fresh lime?
What is the chemical formula for lime wash?
What is the common name for Ca OH 2?
What is lime juice?
Lime juice is the liquid extracted from limes, which are small, green citrus fruits. It is a popular ingredient in cooking, baking, and beverage preparation. Lime juice is known for its tart and citrusy flavor, which can add brightness and acidity to a variety of dishes and drinks.
What is the pH level of a lime?
Limes are an acidic fruit, with a pH of around 2.2, this is because they contain citric acid. This isn’t necessarily bad, because the pH of your stomach acid will range from around 1.5 to 3.5, so the pH of the lime won’t affect your body. However, it could affect your teeth and cause enamel erosion. This is why it is important to limit your intake of highly acidic foods and to drink water after consuming highly acidic food, so the acid doesn’t linger and damage your enamel.
How many calories are in lime juice?
According to the USDA, the juice of a single lime that weighs approximately 44 grams contains 11 calories and 3.7 carbohydrates. It has approximately 0.74 grams of sugar and 0.13 grams of protein. The nutritional value of lime juice can support the heart, reduce asthma, and promote healthy skin.
What are the different types of lime juice?
Lime juice primarily comes from two main varieties of limes: Persian limes (also known as Tahiti limes) and Key limes. These varieties have some differences in flavor, size, and culinary uses. Here’s a brief overview of each: Appearance: Larger in size compared to Key limes, with a bright green color.