# Calculate the valency of the element?

1. May 21, 2013

### avistein

1.The equivalent weight of an element is 4.It's chloride has a V.D.=59.25.Find out the valency of the element

2. Relevant equations

3.Molecular wt=108.50 u.Then how to proceed?

2. May 22, 2013

### Staff: Mentor

What is VD?

3. May 22, 2013

### Staff: Mentor

Venereal Disease?

4. May 22, 2013

### Saitama

I think VD is Vapour Density.

:tongue:

5. May 23, 2013

### Staff: Mentor

Slightly more likely than Mark's suggestion , but if so, we will need units to be able to calculate anything.

6. May 24, 2013

### avistein

@Borek and all others,V.D is Vapour Density.

7. May 24, 2013

### avistein

@Borek,what units do you need?

8. May 24, 2013

### Staff: Mentor

Units of vapour density - is it in stones per cubic mile, or pounds per barrell, or something else? Without units number you listed doesn't make any sense.

9. May 25, 2013

### Saitama

:rofl:

At least in the book I follow, the author has never mentioned the units of vapour density even though it is defined as Molecular weight/2.

10. May 25, 2013

### sankalpmittal

See the original definition of Vapour Density. Its just the ratio of density of substance with respect to hydrogen, or ratio of mass of substance to the mass of same volume of hydrogen under same condition of temperature and pressure. Ratio does not have any unit, just like the relative molecular mass. Note: I used "substance" word. Better replace it with "given gas".

When you apply laws of gases, etc.. you get the modified definition of vapour density as Molecular weight/2. That Molecular Weight is in fact Relative Molecular Weight.

11. May 26, 2013

### mishrashubham

This isn't even an attempt since by definition, vapour density is numerically equal to half the molar mass.

Think what the relationship between equivalent weight and molar weight is. Also instead of valency you might want to use the term 'equivalence factor' although note that IUPAC has discouraged the use of equivalence concept.