Chapter 3.4, Problem 7RQ

Interpretation Introduction

Interpretation: The given table needs to be completed.

Concept introduction: A table in chemistry, where all elements are arranged by increasing atomic number is described as periodic table. There are more than 100 elements in the world and the periodic table classifies these elements.

Answer to Problem 7RQ

The required table:

Name	Symbol	Atomic Number	Metal or Non-metal	Family
Lithium	Li	$3$	Metal	Alkali metal
Bromine	Br	$35$	Non- metal	Halogens
Krypton	Kr	$36$	Non-metal	Nobel gas
Magnesium	Mg	$12$	Metal	Alkaline earth metal
Copper	Cu	$29$	Metal	Transition

Explanation of Solution

Protons are defined as a positively charged $\left(+ve\right)$ sub-atomic particles/ units found in the nucleus of an atom. Number of Protons are equals to the atomic number.Symbol of any chemical is a short hand way to represent any element. It tells us what atom it is. First letter code for a chemical element is always capital.

The periodic table is a very useful way to arrange elements. In a periodic table, the border line between the metals and non-metals are defined as “stair-step” line. Elements that are on the right side of stairs, called non-metals and elements that are on right side of stairs, called metals.  Elements along the stair-step line are known as metalloids.In the periodic table vertical columns are known as families.

By using the periodic table is given below:

Name	Symbol	Atomic Number	Metal or Non-metal	Family
Lithium	Li	$3$	Metal	Alkali metal
Bromine	Br	$35$	Non- metal	Halogens
Krypton	Kr	$36$	Non-metal	Nobel gas
Magnesium	Mg	$12$	Metal	Alkaline earth metal
Copper	Cu	$29$	Metal	Transition

Conclusion

In a periodic table, elements are divided according to their chemical behaviour.