Question

What type of a chemical reaction takes place when,
(i) Limestone is heated?
(ii) Proteins are converted into amino acids?
A) In both (i) and (ii) , a combination reaction takes place
B) In (i), a decomposition reaction takes place while in (ii), a combination reaction takes place
C) In both (i) and (ii), a decomposition reaction takes place
D) In (i), a combination reaction takes place, while in (ii), a decomposition reaction takes place

Answer 1

Hint :Limestone is a sedimentary rock that is mostly composed of calcium carbonate $ CaC{O_3} $ . It was formed $ 300 $ million years ago at the bottom of a sea. Proteins are made up of amino acids, which are small organic molecules with an alpha (central) carbon atom connected to an amino group, a carboxyl group, a hydrogen atom, and a variable portion known as a side chain.

Complete Step By Step Answer:
(i) Limestone is heated
Calcium carbonate is broken down into calcium oxide and carbon dioxide as limestone is burned in a kiln. Thermal decomposition is the name for this kind of reaction. Calcination is the term for this procedure. Quicklime is formed as limestone is burned and transforms into calcium oxide.
 $ CaC{O_3} \to CaO + C{O_2} $
(ii) Proteins are converted into amino acid
A key source of amino acids is dietary protein. Dietary proteins are broken down into amino acids or short peptides that can be processed by the stomach and transferred into the bloodstream. Degradation of damaged or unnecessary cellular proteins is another type of amino acids. Proteins also undergo decomposition reactions to form amino acids. The reaction is as follows:
 $ {( - A\min o.acid - )_n} \to n.Amino\;acids $
In both the cases the reaction is a decomposition reaction.
Hence, the correct option is C) In both (i) and (ii), a decomposition reaction takes place.

Note :
Limestones with clay content are used in the manufacture of cement. Limestone concrete is also used in the building of roads and railroads. Infusion solutions, as well as tablet and granulated formulations, are used to deliver amino acids, which are an important component of current medical therapies. Amino acids aid in the increase of chlorophyll content in plants, resulting in increased photosynthesis.