Q. 4.36 - An Introduction to General, Organic, and Biological Chemistry

Question

Write the atomic symbol for the isotope with each of the following characteristics:

a. An oxygen atom with $10$ neutrons 

b. $4$ protons and $5$ neutrons

c. $25$ electrons and 28 neutrons 

d. A mass number of $24$ and $13$ neutrons

e. A nickel atom with $32$ neutrons

Step-by-Step Solution

Answer

(a) The required atomic symbol is, ${}_8{}^{18}O$

(b) The required atomic symbol is, ${}_4{}^{9}Be$

(c) The required atomic symbol is, ${}_{25}{}^{53}Mn$

(d) The required atomic symbol is, ${}_{11}{}^{24}Na$

(e) The required atomic symbol is, ${}_{28}{}^{60}Ni$

Part (a) Step 1: Given information

We need to find out the atomic symbol of the oxygen atom having $10$ neutrons  

Part (a) Step 2: Simplify

We know that,

Atomic no. of oxygen atom is, $Z=8$

And mass no. is equal to the sum of no. of protons and no. of neutrons

Therefore, mass no. is, $A=8+10$$=18$

Also, standard representation of an element is, ${}_Z{}^{A}X$

Hence, the required atomic symbol is, ${}_8{}^{18}O$

Part (b) Step 1: Given information

We need to find out the atomic symbol of the isotope having $4$ protons and $5$  neutrons 

Part (b) Step 2: Simplify

We know that,

No. of protons are equal to atomic no. of the element.

So, atomic no. is, $Z=4$

And mass no. is equal to the sum of no. of protons and no. of neutrons

Therefore, mass no. is, $A=4+5$

Also, standard representation of an element is, ${}_Z{}^{A}X$

Here, $X$ is $Be$(Beryllium)

Hence, the required atomic symbol is, ${}_4{}^{9}Be$

Part (c) Step 1: Given information

We need to find out the atomic symbol of the isotope having $25$ electrons and $28$ neutrons  

Part (c) Step 2: Simplify

We know that,

No. of electrons are equal to atomic no. of the element.

So, atomic no. is, $Z=25$

And mass no. is equal to the sum of no. of protons and no. of neutrons

Therefore, mass no. is, $A=25+28=53$

Also, standard representation of an element is, ${}_Z{}^{A}X$

Here, $X$ is $Mn$(Manganese)

Hence, the required atomic symbol is, ${}_{25}{}^{53}Mn$

Part (d) Step 1: Given information

We need to find out the atomic symbol of the isotope having mass no. of $24$ and $13$ neutrons

Part (d) Step 2: Simplify

We know that,

Mass no. is equal to the sum of no. of protons and no. of neutrons

So, no. of protons are difference between mass no. and no. of neutrons i.e. $24-13=11$

And atomic no. is equal to no. of protons.

Therefore, 

Atomic no. is, $A=11$

And Mass no. is, $Z=24$

Also, standard representation of an element is, ${}_Z{}^{A}X$

Here, $X$ is $Na$(Sodium)

Hence, the required atomic symbol is, ${}_{11}{}^{24}Na$

Part (e) Step 1: Given information

We need to find out the atomic symbol of the nickel atom having $32$ neutrons  

Part (e) Step 2: Simplify

We know that,

Atomic no. of nickel atom is, $Z=28$

And mass no. is equal to the sum of no. of protons and no. of neutrons

Therefore, mass no. is, $A=28+32=60$

Also, standard representation of an element is, ${}_Z{}^{A}X$

Hence, the required atomic symbol is, ${}_{28}{}^{60}Ni$