#1 How are the melting points and boiling points of molecular compounds usually different from ionic compounds.

Covalent Compounds often have Low melting and boiling points due to weaker bonds between

atoms

Click on the picture to see the animation

#2 What information does a molecular formula provide?

A molecular formulatells the types and numbers of atoms ina molecule.

It DOESNOT tell you the way the atoms are combined

H2O (Water)

#3 What are the only elements that exist innature as uncombined atoms? What term isused to describe such elements?

Ne

KrAr

He

Xe

Rn

Only the NOBLE GASES do not normally make compounds. They are known as MONATOMIC

#4 Describe how the molecule whose formula is NOis different from the molecule whose formula is N2O.

NO is one atom ofnitrogen and one of oxygen.

N2O is TWO atoms ofnitrogen and one of oxygen.

#5 Give an example of a diatomic moleculefound in Earth’s atmosphere.

Two Examples:

#6 What information does a molecule’s molecular structure give?

A molecular FORMULA (example: H2O) only tells what atoms and how manyof each are present. It doesn’t show how those atoms are bound together.

A molecular STRUCTURE shows HOW the atoms are bonded and arranged in the molecule:

pictures of bonding

Examples of Molecular structurefor Water