covalent bonding help?

Question

1.Classify each of the following as an atom or a molecule.
a. Be b.Co2 c.N2 d. H2O E. Ne
2.Which of the following are diatomic molecules?
a.CO2 b.N2 c.O d.H2O e.CO
3.What type of elements tend to combine to form molecular compounds?
4.What info. does a molecule's molecular structure give?
5.how do ionic compounds and molecular compounds differ in their relative melting and boiling points?

Answer 1

1) An atom will be represented by a single atomic symbol with no numbers. Be and Ne are atoms. CO2, N2, and H2O are all molecules.

2) A diatomic molecule is one which contains two atoms. It will be represented by either a single atomic symbol followed by a 2, like N2 (meaning two of the same atom bound together) or two different atomic symbols with no numbers, like CO (meaning one of each of two different atoms bound together). N2 and CO are diatomic; the others aren't.

3) Generally nonmetals form covalent bonds; metals prefer to form ionic bonds with nonmetals and metallic bonds with each other.

4) Molecular structure tells you the shape of a molecule, which atoms are connected to which and how they're connected. It can also be used to predict properties such as melting and boiling points and how a molecule will react.

5) Ionic compounds tend to have very high melting and boiling points, and are virtually always solid at room temperature. Molecular compounds vary more widely, but often have low melting/boiling points, and many are liquids or gases at room temperature.

Answer 2

its when atoms of metals share electrons. like, Na an K