Chemistry revision: Arguments for and against quarrying, etc.

Arguments for quarrying

Limestone is quarried on a very large scale in the peak district in derby shire.It is used as a building material , in agriculture, as a raw material to make other materials like glass and to remove acidic impurities from iron in the blast furnace. Therefore, there is a big demand for limestone. Initially, explosives are used to break up the limestone in quarries. Lorries are used to transport the limestone.

There is a big demand for limestone as a building material. Limestone is needed to provide other building materials such as concrete, cement and glass. Limestone is needed as a raw material in industries, e.g. iron industry. It provides employment for local people it brings money into the area.

Arguments against quarrying

Noise pollution from explosions and lorries. Dust pollution The quarry is a scar on the landscape (may reduce number of tourists) Waste materials are unsightly. Habitats of animals and plants (can) get destroyed.

Limestone is mainly composed of the compound calcium carbonate (CaCO3). Other rocks, composed of this compound are chalk and marble. Chalk and limestone are sedimentary rocks, whereas marble is a metamorphic rock. All of these rocks are formed from the shells and skeletons of sea creatures which lived millions of years ago./ The difference in formation of these 3 rocks are the different conditions the Shelly remains were/are subjected to. Chalk and limestone were both formed by compression of the Shelly remains by layers of sediment over millions of years.  Chalk is a softer rock as it has not been compressed as much. Marble is a rock which has been formed by the action of heat on limestone or chalk.

Equations for reactions in the limestone cycle:Calcium carbonate-> Calcium oxide+carbon dioxideCalcium oxide+water->  Calcium hydroxideCalcium hydroxide+carbon dioxide-> Calcium carbonate

Applicants of Acid-carbonate reactions1. Acid rain can react with limestone structures, causing the stone to erode.2. Baking powder contains sodiumhydrogencarbonate and tartaric acid which react when moistened in a cake mixture to produce CO2 which causes cake to rise. 3. Alka-Seltzers contain sodiumhydrogencarbonate and citric acid which react in water to make CO2 - causing it to effervesce.4. Calcium carbonate is needed to neutralize excess acid in soil, water and gas.5. Carbonates are used in antacid tablets to neutralize excess acid which causes indiestion.   

Conclusion for heating different metal carbonates!!!All of these carbonates should have broken down on heating (thermal decomposition) to produce carbon dioxide gas, which turns limewater milky. The solid left after heating is called the metal oxide. 

How rate of decomposition relates to the activity series.The more reactive the metal in the carbonate, the more stable the carbonate is and the less easily it decomposes. The less reactive the metal in the carbonate, the less stable it is, therefore the faster/easier it will decompose.

Both calcium and magnesium are white solids. Zinc oxide is yellow when hot but white when cold. Finally, copper oxide is a black solid.

                                                  Advantages                                                                                                                                                                  DisadvantagesLimestone:                              Attractive building material.                                                                                                                                         Eroded by acid rain resulting in loss of detail.

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