Calcium carbonate or CaCO3 is one of chemical compound found in the rocks as a mineral calcite and aragonite mostly particularly as a limestone, chalk or a marble.

1. www.worldofchemicals.com
www.worldofchemicals.com

2.  Calcium carbonate or CaCO3 is one of chemical compound
found in the rocks as a mineral calcite and aragonite
mostly particularly as a limestone, chalk or a marble.
 Although the fact that they are available in various forms
they are chemically similar but differ physically.
 They differ in terms of whiteness, thickness, purity and
homogeneity.
 Similar to limestone, calcium carbonate is a biogenic rock,
and is more compressed than chalk.
 Calcium-carbonate is a bristly-crystalline, metamorphic
rock alike marble that is formed when chalk or limestone
is re-crystallized.
 Huge sediments of marble are obtained in North America
and in Europe for example in Carrara, Italy, where the pure
white "statuario marble" is found. Calcium
carbonate crystals are also described as calcite.
www.worldofchemicals.com

3.  The massive amount of bulk calcium carbonate used in industry
is obtained by excavating or mining.
 Calcium carbonate can be produced from pure quarried source
which is used for food and pharmaceutical industry.
 However, calcium carbonate is made from oxides of calcium.
 Calcium oxide is dissolved in water to form calcium hydroxide.
 To precipitate the desired solution carbon dioxide is passed
through calcium hydroxide which is signified as precipitated
calcium carbonate (PPC).
 CaO + H2O -> Ca (OH) 2
 Calcium oxide + Water → Calcium hydroxide
 Ca (OH) 2 + CO2 → CaCO3 + H2O
 Calcium hydroxide + Carbon dioxide → Calcium carbonate
www.worldofchemicals.com

4. Geological sources
 Pure forms of calcium carbonate are calcite, aragonite
and vaterite. Significant source of calcium carbonate
include limestone, chalk and marble.
www.worldofchemicals.com
Extraterrestrial source
 There is a strong presence if calcium carbonate on
mars, beyond earth. The evidence proves that calcium
carbonate have been detected in more than one location
specifically in Gusev and Huygens hallows. This shows
indication of presence of liquid water also.

5.  In pure water, calcium carbonate is poorly soluble
i.e. 47 mg/L in normal atmospheric conditions.
 The equilibrium reaction of the solution is shown
by the equation.
 Calcium carbonate -> Calcium ions + Carbonate
ions
 The product for this equation is [Ca2+] [CO3
2−]
www.worldofchemicals.com

6.  The foremost usage of calcium carbonate is in
construction industry, moreover as a material for
buildings or as limestone for roads and also as
component of cement.
 Yet, since weathering is mainly caused by acid rain,
calcium carbonate in the form of limestone is not used
in building but it is only utilized as a raw/primary
material for building substances.
 It is also used for purification of iron from iron ore in a
furnace.
 Carbonates are calcined to form calcium oxide. Calcium
oxides forms a slag i.e. stony waste matter of metals of
impurities and extracted purified iron.
www.worldofchemicals.com

7.  Sucrose which is commonly known as table sugar contains
two reducing sugars moieties fructose and glucose. These
reducing sugar are joined by their glycosidic bond in such
a way as to prevent the glucose isomerising to aldehyde,
or the fructose to alpha-hydroxy-ketone form. Sucrose is
thus a non-reducing sugar which does not react with
Benedict's reagent.
 Sucrose still indirectly can produce a positive result with
Benedict's reagent if heated with dilute hydrochloric
acid(HCl) prior to the test. The acidic conditions and heat
break the glycosidic bond in sucrose through hydrolysis
process. The products of hydrolysis process are reducing
sugars (glucose and fructose) which can be detected by
Benedict's reagent.
www.worldofchemicals.com

8. Thank You
To read this article follow the link:
https://goo.gl/C14Dzp
www.worldofchemicals.com