Ch5.8

Question 1

What are molecular compounds made of?

Answer 1

Two or more nonmetals bonded by covalent bonds.

Question 2

How is the first element named in a molecular compound?

Answer 2

By its element name (e.g., carbon in CO₂).

Question 3

How is the second element named in a molecular compound?

Answer 3

Using the stem of its name + “-ide” (e.g., dioxide for O₂).

Question 4

What are the prefixes for 1–5 atoms in molecular compounds?

Answer 4

1 = mono-, 2 = di-, 3 = tri-, 4 = tetra-, 5 = penta-.

Question 5

When is the prefix “mono-” omitted?

Answer 5

It is omitted for the first element if only one atom is present.

Question 6

What happens to the “a” or “o” in prefixes before vowels?

Answer 6

It is usually dropped (e.g., tetraoxide → tetroxide).

Question 7

Should molecular formulas be reduced to lowest ratios?

Answer 7

No, molecular compounds are not reduced (e.g., N₂O ≠ NO).

Question 8

What is the name of H₂O, NH₃, CH₄, and H₂O₂?

Answer 8

Water, ammonia, methane, and hydrogen peroxide.

Question 9

What kind of bonds do polyatomic ions have internally?

Answer 9

Covalent bonds.

Question 10

What is an example of a compound with both covalent and ionic bonds?

Answer 10

Sodium nitrate (NaNO₃) – ionic compound with a covalently bonded polyatomic ion.