Explanation:

Vapour density is defined as the ratio of the molecular mass of the gas to the mass of an equal volume of hydrogen gas under the same conditions of temperature and pressure.

Vapour density of the volatile chloride of divalent metal is given as 59.5.

To find the equivalent mass of metal, we need to use the following formula:

Equivalent mass = Molecular mass / Valency

Step 1: Find the molecular mass of the compound

Molecular mass = 2 x Atomic mass of metal + Atomic mass of chlorine

Step 2: Find the valency of the metal

The valency of the metal can be determined from the formula of the compound. For a divalent metal, the formula will be MX2, where M is the symbol for the metal and X is the symbol for the chloride ion.

Step 3: Calculate the equivalent mass

Using the formula, we get:

Equivalent mass = Molecular mass / Valency

Equivalent mass = (2 x Atomic mass of metal + Atomic mass of chlorine) / 2

Equivalent mass = Atomic mass of metal + (Atomic mass of chlorine / 2)

Now, let's substitute the given values in the formula:

59.5 = Molecular mass / (2 x Valency)

Valency = 2

Therefore, the formula of the compound is MX2.

Now, using the formula for equivalent mass, we get:

Equivalent mass = (2 x Atomic mass of metal + Atomic mass of chlorine) / 2

Equivalent mass = Atomic mass of metal + (Atomic mass of chlorine / 2)

Equivalent mass = Atomic mass of metal + 35.5

Therefore, the equivalent mass of the metal is (59.5 x 35.5) / 2 = 1054.25 / 2 = 527.125 g/mol.

Hence, the equivalent mass of the metal is 527.125 g/mol.

59.5