Question

Use Lewis theory to determine the formula for the compound that forms between each of the following pairs of elements.

PART A.

Ca and Te

Express your answer as a chemical formula.

PART B.

Ba and Cl

Express your answer as a chemical formula.

PART C.

K and Te

Express your answer as a chemical formula.

PART D.

In and O

Express your answer as a chemical formula.

Answer 1

Part A:

Electronic configuration of Calcium: [Ar]4S²

Electronic configuration of Tellurium: [Kr]4d¹⁰5S²5P⁴

Calcium has 2 valency electrons and to get octet configuration, it has to lose 2 electrons.

Tellurium has 6 valency electrons and to get octet configuration, either it has to lose 6 electrons or gain 2 electrons.

Calcium loses two electrons and Tellurium gains these two electrons. Both the atoms, Calcium and Tellurium gets inert gas configuration.

It's formula is CaTe

Part B:

Electronic configuration of Barium is [Xe]6S²

Electronic configuration of Chlorine is [Ne]3S²3P⁵

Barium has 2 valence electrons and chlorine has 7 electrons in its valency shell.

Barium has to lose 2 electrons to get octet configuration and chlorine requires one electron to get octet configuration.

Formula of barium Chloride is BaCl_​​​2

Part C:

Electronic configuration of Potassium: [Ar]4S¹

Electronic configuration of Tellurium: [Kr]4d¹⁰5S²5P⁴

Potassium has 1 valency electron and to get octet configuration, it has to lose 1 electron.

Tellurium has 6 valency electrons and to get octet configuration, either it has to lose 6 electrons or gain 2 electrons.

Two Potassium atoms lose one electron each and one Tellurium atom gains these two electrons. Both the atoms, potassium and Tellurium gets inert gas configuration.

It's formula is K₂Te

Part D:

Electronic configuration of Lanthanum : [Xe]5d¹6S²

Electronic configuration of oxygen : [He]2S²2P⁴

Lanthanum has 3 electrons in its valency shell and oxygen has 6 electrons.

It's formula: La₂O₃