Chapter 42, Problem 1CQ

To determine

(a)

The isotopes from the given atoms $\text{O}\text{,}\text{O}\text{,}\text{F}\text{,}\text{N}\text{e,}\text{N}\text{e}$.

Answer to Problem 1CQ

Solution:

Isotopes are $\text{O}\text{ and}\text{O}\left(Z=8\right);\text{N}\text{e and }\text{N}\text{e (Z=10)}$.

Explanation of Solution

Isotopes are atoms having the same atomic number (Z) but having the different mass number (A). In our case, both $\text{O}\text{ and}\text{O}$ are having same atomic number Z = 8 and different mass number A = 18 and A = 16 respectively. Also, $\text{N}\text{e and }\text{N}\text{e }$ are having same atomic numbers Z = 10.

Conclusion:

Atoms having a same atomic number (Z) are known as isotopes.

To determine

(b)

The isobars from the given atoms- $\text{O}\text{,}\text{O}\text{,}\text{F}\text{,}\text{N}\text{e,}\text{N}\text{e}$.

Answer to Problem 1CQ

Solution:

Isobars are $\text{O}\text{,}\text{F}\text{,}\text{N}\text{e}\text{.}$

Explanation of Solution

Isobars are atoms having the different atomic number (Z) but having the same mass number (A). In our case, $\text{O}\text{,}\text{F}\text{,}\text{N}\text{e}$ are having same mass number A = 18.

Conclusion:

Atoms having a same mass number (A) are known as isobars.

To determine

(c)

To determine the atoms having same chemical properties from the given atoms.

$\text{O}\text{,}\text{O}\text{,}\text{F}\text{,}\text{N}\text{e,}\text{N}\text{e}$.

Answer to Problem 1CQ

Solution:

Atoms having the same chemical properties are $\text{O}\text{ and}\text{O};\text{N}\text{e and }\text{N}\text{e }$.

Explanation of Solution

Isotopes of the same element are chemically same. In our case, Isotopes are $\text{O}\text{ and}\text{O}\left(Z=8\right);\text{N}\text{e and }\text{N}\text{e (Z=10)}$.

Conclusion:

Chemical properties of isotopes of the same element are same.

To determine

(d)

To determine the atoms having the same number of neutrons from the given atoms.

$\text{O}\text{,}\text{O}\text{,}\text{F}\text{,}\text{N}\text{e,}\text{N}\text{e}$.

Answer to Problem 1CQ

Solution:

Atoms having the same number of neutrons are $\text{O}\text{ and}\text{N}\text{e ; }\text{O}\text{ and}\text{N}\text{e}$.

Explanation of Solution

As we know in an atom n + p = A where n is the number of neutrons, p is the number of protons and A is the mass number. Also, the number of protons in an atom is equal to its atomic number. So, we can say n + Z = A. So, the number of neutrons is equal to mass number (A) – atomic number (Z). In case of $\text{O}\text{ and}\text{N}\text{e }$ number of neutrons are 10($\text{O}\text{ (n = 18 - 8 = 10) and}\text{N}\text{e (n = 20 - 10 = 10) }$) also $\text{O}\text{ and}\text{N}\text{e}$ number of neutrons are 8($\text{O}\text{ (n = 16 - 8 = 8) and}\text{N}\text{e (n = 18 - 10 = 8)}$).

Conclusion:

Atoms having the same difference in the mass number (A) and atomic number (Z) will have the same number of neutrons.