hat are likely formulas for the following molecules? Supply the missing digit. Choose 1 if the element appears in the formula as a single atom. Hydrogens are bonded to the preceeding atom in the formula. (a) CH3OH? (b) CH? I (c) AlCl?

(a) CH3OH1 (b) CH3I (c) AlCl3

Explanation:

Each molecule can be explain knowing the valence for each element. The valence refers the number of bond the element can do.

(a) CH3OH, methanol

oxygen has valence 2. So just one hydrogen can be bond to the oxygen because the other bond is formed with the carbon

(b) CH3I, yodoform

carbon has valence 4 (4 bonds). If there is o1 bond with iodine, it needs 3 hydrogen to form the 4 bonds.

(c) AlCl3, aluminium trichloride

Aluminium has valence 3, that is the reason the number of chlorines needed is 3.

The formulas are:

a) CH3OH1

b) CH3I

c) AlCl3

Explanation:

We have some organic and inorganic compounds. We have to analyze each one taking into account the following global rules:

1 - Carbon can be bonded to four atoms.

2 - Oxygen can be bonded to two atoms.

3 - Halogens usually have a - 1 valence, which means they can be bonded to one atom.

4 - Hydrogen can be bonded to one atom.

5 - Metals can be multivalent depending on the configuration. Aluminum can be + 2 or + 3.

Now, we will analyze each one of those formulas:

a) CH3OH?

Carbon is bonded to three Hydrogen and one Oxygen. Oxygen is bonded to one Carbon and an unknown number of hydrogens. As Oxygen can be bonded only to two atoms, the Hydrogen number must be one.

Finally, the formula is CH3OH1

b) CH? I

Carbon is bonded to one halogen and some hydrogens. Carbon can be bonded up to four atoms, one halogen. So, the three other atoms should be Hydrogens.

Finally, the formula is CH3I.

c) AlCl?

This inorganic compound is easy to study through the valence number. Aluminum can have a + 3 valence number. Chlorine has - 1 Valence. When we have two compounds it is easy to form an adequate formula.

We have

Al (+3) Cl (-1)

The right formula can be obtained by changing the valence numbers to the coefficients of the atoms.

Al (1) Cl (3).

Finally, the formula is AlCl3.