Q. 4.7 - An Introduction to General, Organic, and Biological Chemistry

Question

Identify the group or period number described by each of the following :

a. contains $\mathrm{C}$,$\mathrm{N}$and $\mathrm{O}$              b. begins with helium

c. contains the alkali metals     d. ends with neon

Step-by-Step Solution

Answer

a. Period $2$ contains data-custom-editor="chemistry" $\mathrm{C},\mathrm{N}$anddata-custom-editor="chemistry" $\mathrm{O}$ elements

b. Group $8A\left(18\right)$ begins with helium

c. Group $1A\left(1\right)$ contains the alkali metals

d. Period $2$ ends with neon

Part (a) Step 1 : Given information

We have to Identify the group or period number which contains $\mathrm{C}$,$\mathrm{N}$ and $\mathrm{O}$.

Part (a) Step 2 : Simplification

• Analysing the periods and groups of modern periodic table.
• According to the modern periodic table period $2$ contains $\mathrm{C}$,$\mathrm{N}$and $\mathrm{O}$

Part (b) Step 1 : Given information

We have to Identify the group or period number which begins with helium.

Part (b) Step 2 : Simplification

• Analysing the periods and groups of modern periodic table.
• According to the modern periodic table Group $8A\left(18\right)$ begins with helium.

Part (c) Step 1 : Given information

We have to Identify the group or period number which contains the alkali metals.

Part (c) Step 2 : Simplification

• Analysing the periods and groups of modern periodic table.
• According to the modern periodic table Group $1A\left(1\right)$ contains alkali metals.

Part (d) Step 1 : Given information

We have to Identify the group or period number which ends with neon.

Part (d) Step 2 : Simplification

• Analysing the periods and groups of modern periodic table.
• According to the modern periodic table Period $2$ ends with Neon.