Question

${\text{Ca(HC}}{{\text{O}}_{\text{3}}}{{\text{)}}_{\text{2}}}$ is:
A. A molecule
B. A mixture of compounds
C. An isotope
D. An isomer
E. An acid salt

Answer 1

In the question, we are given the different terms like a molecule, a mixture of compounds, an isotope, an isomer, and an acid salt. The most different term is an acid salt. If we define an acid salt, we can say that it is made up of an alkali metal, and contains one or more hydrogen atoms.

Complete step by step answer:
-Now, we will discuss all the terms given in the question. First, we have the term a molecule.
-If we define a molecule, we can say that when two or more atoms of the same element are combined together like ${{\text{O}}_{\text{2}}}$.
-Second, we have the term a mixture of compounds. Now, if we discuss this term, we can define it as the substance formed by two or more elements; when they are bound to each other chemically.
-If we see the examples of compounds i.e. NaCl, HCl, ${{\text{H}}_{\text{2}}}{\text{O}}$ and many more.
-Third, we have to discuss the term an isotope. We can say that when an element has the same number of protons but there are a different number of neutrons.
-We can understand it from an example like -${}_{\text{1}}^{\text{1}}{\text{H,}}{}_{\text{1}}^{\text{2}}{\text{H,}}{}_{\text{1}}^{\text{3}}{\text{H}}$. -These three are isotopes of hydrogen. Here, we can observe that the subscript is the same, but the superscript number is different.
-Fourth we have to discuss the term an isomer. Isomer can be easily understood from the example, i.e.

-Now, the structures drawn are butane and isobutane. We can see that the molecular formula and the number of atoms are the same in both the structures but the arrangement of atoms is different.
-So, we can say that butane, and isobutane are isomers of each other.
-Now, we have the last term an acid salt, as mentioned it is made up of alkali or alkaline earth metal combined with one or more atoms of hydrogen.
-As we know that buffers used in the solution are acid salts. The examples are sodium bicarbonate, calcium bicarbonate, and many more.
-In the last, we can conclude that ${\text{Ca(HC}}{{\text{O}}_{\text{3}}}{{\text{)}}_{\text{2}}}$ is an acid salt.
Hence, the correct option is E.

Note: Don’t get confused as isotopes are also defined as the atoms of an element having the same atomic mass, but differs in the mass number. When we represent an element the subscript denotes the atomic number, and the superscript denotes the mass number as mentioned in the isotopes of hydrogen.