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.
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
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.
An Experiment to Find Out How Much Gas is Given Off When Hydrochloric Acid and Marble Chips React
Investigation of the reaction between hydrochloric acid and marble chips A chemical reaction is when two or more substance called reactants are chemically bonded to form a new product, as a result of the process, for a reaction to take place, the particles must have enough kinetic energy to collide and form new bonds , this is called a successful collision. The minimum amount of energy needed for a successful collision is activation energy, which is “The energy that an atomic system must acquire before a process can occur”. Chemical reaction is different to a physical reaction, chemical reaction are not reversible and results in a new product, however a physical reaction can be easily reversed as it only changed its state. The activation energy is able to loosen particles and enable them to from new bonds to produce new products. The faster the molecules are moving the bigger the chance of a successful collision, so the faster and stronger the reaction will be , the more kinetic energy a reactant has the easier it is for the new bonds the collide and produce new bonds.
How the change of Hydrochloric Acid concentration affects the rate of reaction with Marble Chips
It will be when there is too much HCl for the marble chips to dissolve
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.
Investigating the Rate of Reaction Between Marble Chips and the Varying Concentrations of Hydrochloric Acid
It is unknown when people first knew about calcium and when people used compounds of calcium. Limestone is a compound of calcium and Limestone was usually used for buildings. The common name for limestone is calcium carbonate. Early Greeks and ancient Egyptians used mortar which was made from heated limestone. It was named for its natural occurrence in limestone with was a common building material, which in itself is an oxide of calcium with the molecular formula being CaCO3. The Latin name for limestone being calx, hence
An investigation into how changing one variable influences the rate of reaction between marble chips and dilute Hydrochloric acid
Compared to the 0.5 M hydrochloric acid that was less concentrated, the more concentrated 2 M hydrochloric acid c...
Coastal Erosion operates at different rates and different times. Limestone rock is eroded slower than sedimentary rock. The cliff at Muriwai made of sedimentary rock was eroded back to expose 'Fisherman's Rock' - the shore platform which, made of limestone -- tended to erode back slower than the cliff.
"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).
acids. I only tried the 1 molar acid, but if I were to repeat the