What is isotopes and isobars...?

Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom

Isobars are atoms of different chemical elements that have the same number of nucleons. Correspondingly, isobars differ in atomic number but have the same mass number. An example of a series of isobars would be ⁴⁰S, ⁴⁰Cl, ⁴⁰Ar, ⁴⁰K, and ⁴⁰Ca

Step-by-step explanation:

ISOTOPES:

Elements having same atomic number but different atomic masses are known as Isotopes.

Example:

Carbon-12, Carbon-13, Carbon-14 are thee isotopes of carbon atom. Here 12, 13 and 14 are the atomic masses of isotopes of carbon respectively. Since, atomic number is the unique property of an atom, thus the atomic number of carbon is 6 even in the case of three types of carbon (isotopes)

126Carbon, 136Carbon, 146Carbon are 3 isotopes of Carbon.

Hydrogen-1, Deuterium–2, Tritium-3 are three isotopes of hydrogen.

ISOBARS:

Elements having same atomic mass and different atomic numbers are known as Isobars.

Example:

4018Ar (Argon) and 4020Ca (Calcium)

Both the elements have same atomic mass equal to 40 but different atomic numbers, i.e. argon has atomic number equal to 18 and calcium has atomic number equal to 20.

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step-by-step explanation:

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for this case we must apply distributive property to the following expression:

the distributive property states that:

then, when applying the property we have to multiply the -2 for each term within the parenthesis: