Lecture: Molecules and Compounds

Compounds and Molecules: A chemical structure that is made of two or more atoms that are bonded together.

Examples of Compounds and Molecules

H2O, O3, Ba(OH)2, and H2SO4

The numbers after the Atomic Symbol tells you how many atoms of that element are needed to make the compound. No number after an Atomic Symbol is equal to 1.

H2SO4 is made of the following elements and how many of that element are needed to build it.H: 2S: 1O: 4

Calculate the types of elements and number of each element to make the following compound.NH3OH

NH3OH

N: Nitrogen = 1

H: Hydrogen = 4

O: Oxygen = 1

CO is not the same as Co. CO is the compound carbon monoxide (1 carbon atom and 1 oxygen atom). Co is the element cobalt.

Mg(OH)2

Mg

O

H

Mg(OH)2

Mg: 1

O

H

Mg(OH)2

Mg: 1

O: 1

H

Mg(OH)2

Mg: 1

O: 1 x 2= 2

H

Mg(OH)2

Mg: 1

O: 1 x 2= 2

H: 1 x 2= 2

Complete this problem on your worksheetHomework Example: SO2

Answer:Sulfur=1 Oxygen =2