Investigating How Varying the Concentration of Hydrochloric Acid Affects the Decomposition of Marble Chips
My aim for this experiment is to discover how varying the concentration of hydrochloric acid (HCl) affects the decomposition of marble chips (calcium carbonate).
The equation for this reaction is:
[IMAGE] CaCO 3 +2HCl CaCl 2 +H 2 O+CO 2
Background knowledge ( Found via the internet and 'Key Science Chemistry' by Eileen Ramsden)
What is limestone?
Limestone and chalk are sedimentary rocks with their main compound being calcium carbonate. Limestone is mainly found underneath the sea as it is formed by the skeletons and shells of tiny sea animals compressed under many layers of other materials.
We are being supplied with marble chips instead of limestone. This is because acid rain will wear away limestone for many years, and we haven't got that much time, so that is why we are using marble chips instead. This will not affect the reaction as marble is of the same composition as limestone and chalk, calcium carbonate (CaCO 3 ) but because of high temperatures and pressures has been turned into a metaphoric rock.
What is weathering?
There are many types of weathering: Chemical weathering, physical weathering which includes (wind abrasion and ice).
However only chemical weathering- acid rain will be used in this experiment.
Acid rain (Chemical weathering) therefore,
[IMAGE] Acid + carbonate salt + CO 2 + H 2 O
Acid Rain
Acid rain is caused by pollutants and chemicals released into the atmosphere. The rainwater is already naturally acidic because of the carbon dioxide dissolved in it, however sulphur dioxide given out by car exhausts and power stations, meet with the air to make sulphur trioxide.
The shelf-edge includes carbonate-to-clastic facies transition and tectonic uplift and erosion of the carbonates followed by deposition of the clastics. The Saint Peter Sandstone is a well-sorted, almost pure quartz arenite deposited during a major mid-Ordovician low stand. Clastics spread across an exposed carbonate platform by transportation. This is shown by the well-rounded, frosted texture of the quartz grains.
Investigating How the Concentration of Hydrochloric Acid Affects the Speed of the Reaction with Marble Chips
This sedimentary rock has hardened over the many years with sand shells, small pebbles, grains of sand and rocks of various sizes. In comparison to our 4.5 billion year old Earth, these sand shells might as well be brand new, when in reality they could be up to 1,000 years old. If the sandstone were to be replaced with calcite it would completely change the subclass of rock, it would then be chemical & organic limestone. The variation in sand stone is due to different rates of deposition and change in patterns of the sediment movement (Mc Knight, p. 384). These tightly compacted varying stones and shells will be weathered away by wind and waves over time and could eventually be reduced to a rock the size of your hand.
Quartzite is a non-foliated metamorphic rock. This rock is intrusive and forms when exposed to extreme amounts of heat and pressure. Over a billion years ago, there was an ocean where Kamiak Butte is. This ocean floor was made of sand, as time went on oceans receded and the exposed sand underwent processes that turned it into sandstone – or as we learned in class the process of lithification. Years later, this sandstone would morph into the quartzite that is present now.2
Acid rain has been proven to have damage forests, fresh waters and soils, killing insect and aquatic life-forms. It also causes damage to buildings and impacts on human health. Many people do not know what acid rain actually is. Acid rain is any form of precipitation that is unusually acidic, low pH levels, higher than normal amounts of sulfuric and nitric acid, occurs naturally and from man made sources. Forms when gases react in the atmosphere with water, oxygen, and other chemicals (what is acid rain?). The only water that will not have some amount of acidity is pure water. Pure water has a pH of 7 which is neutral; regular, unpolluted rain water has a pH of around 5.6. The acidity in rain water comes from the presence of Carbon Dioxide, Nitrogen Oxide, and Sulfur Dioxide. CO2 reacts with water to form carbonic acid. Nitrogen and water react during lightning storms, forming Nitric Oxide. NO is then oxidized to form N02. The NO2 reacts with water to form nitric acid. Due to this, the pH is lowered to be slightly acidic (Acid Rain). Acid rain can occur naturally in the environment, but the problem occurs when human interaction is the cause of the acidic levels.
Many different organisms, including mollusks, sponges, and worms, help shape reefs, but hard corals and various algae are the major architects. In effect, the corals build limestone, because their skeletons are made of Calcium Carbonate. The skeletons deposited by these corals and other organisms accumulate, along with sand and other debris, to form the backbone of the reef. Over tens of thousands of years, chemical and mechanical changes turn the reef into true rock (Alstyne and Paul, 1988).
Rate of Reaction Between Marble Chips and Hydrochloric Acid. The aim of this experiment is to find out how different variables affect the rate at which the reaction between Marble chips (CaCO ) and Hydrochloric acid (HCl) is used. There are many variables that affect the rate of this reaction such as the following. 1.
...y comes from the Balcones Escarpment. Larger crushed rock from this area is used as a base layer for roads and buildings, to protect them from the shifting soils. Very pure limestone is procesed into lime, wich is then used in a wide variety of agricultural, industrial, and construction activities. Other rocks crushed for building materials include basalt, used for railroad track beds, and marble, used for fancy terrazzo floors.
Acid rain is polluted rain, snow, or fog. The burning of fossil fuels, base metal smelting, and fuel combustion in vehicles emits sulfur dioxide (SO2) and nitrogen oxides (NOx) (FAQ Acid Rain). These gases enter the atmosphere and transform into sulfuric acid (H2SO4) and nitric acid (HNO3), which then acidify the water vapor. The acidified water vapor will then fall to the earth as acid rain, snow, or fog (Acid Rain and the Aquatic). This is called ìwet depositionî. There is also ìdry depositionî which falls to the ground in particulate form (FAQ Acid Rain).
Ca(NO3)2 and Na2(C2O4) are combined to produce calcium oxalate stone samples. Next Ca(NO3) and sodium phosphate are utilized to synthesize calcium phosphate stone samples. For the synthesis of the calcium oxalate stones, 11 grams of Ca(NO3)2 is dissolved in 225mL of DI water. 8.00 grams of Na2(C2O4) is dissolved separately in 200mL of DI water. The two aqueous solutions were mixed separately in order to ensure their complete homogeneous transition. Once each solution is completely dissolved, the aqueous solutions of Ca(NO3)2 and Na2(C2O4) are mixed together to form the precipitate , which produces the Calcium oxalate stone
An investigation into how changing one variable influences the rate of reaction between marble chips and dilute Hydrochloric acid
Rain forms when water vapor condenses and falls, the more it condenses the more it falls. Some raindrops are not pure and are filled with other materials, this is known as acid rain. Acid rain is a huge problem all over the world. Acid rain is mixture of chemicals, like fossil fuels and the atmosphere, it then comes down as rain, snow, hail, and sleet. The burning of fossil fuels is the main cause of acid rain. When oil and coal are burned they create sulfur dioxide, nitric oxide, and nitrogen dioxide. (" Acid Rain | US EPA") The mixture of all the chemicals and heavy winds blow the compounds across many borders.
"Acid rain describes any form of precipitation with high levels of nitric and sulfuric acids. It can also occur in the form of snow, fog, and tiny bits of dry material that settle to Earth." (Howard, 2014). The pH of pure water is 7 and, naturally, the pH of rain water is slightly acidic; usually around a 6 on the pH scale. Rain is considered acid rain when its pH is lower than 5.6. Acid rain is not acid falling from the sky like some people seem to assume. It is rainfall that is mixed with elements and gases that then cause the moisture to become more acidic than usual. The release of sulfur dioxide and nitrogen oxides are the result of the combustion of fossil fuels and, therefore, two of the primary chemicals found in the production of acid rain. "It is thought that acid rain began around 1950 to 1955 in the Northeastern United States" (Likens, 1996).
Every day, factories, power plants, and even your cars emit dangerous chemicals into our atmosphere. When these chemicals mix with the moisture in our air, acid rain is produced. Acid rain falls onto lakes, rivers, fields, and forests destroying them. Acid rain is a serious environmental concern, however, it can be prevented.
Acid rain has a harmful impact on the environment which is a serious environmental problem that affects large parts of the United States and Canada. Acid rain is particularly damaging to lakes, streams, forests and the plants and animals that live in these ecosystems. Acid rain is referring to a mixture of wet and dry deposition from the atmosphere containing higher than normal amounts of nitric and sulfuric acids. They are oxidized in the air until they are converted to sulfuric and nitric acids. These acids are then captured by raindrops which fall to the earth as acid precipitation. This process is called deposition. We know this as acid rain, but we can have acidic snow or hail and even acidic dust particles falling from the sky. It can occur in natural resources, such as volcanoes and decaying vegetation, and man-made sources, primarily of sulfur dioxide and nitrogen oxides resulting from fossil fuel combustion.