Douglasite is a mineral with the formula 2kcl # fecl2 # 2h2o. calculate the mass percent of douglasite in a 455.0-mg sample if it took 37.20 ml of a 0.1000-m agno3 solution to precipitate all the cl2 as agcl.

Answer : The mass percent of Douglasite is 63.75 %

Explanation :

First we have to calculate the moles of .

As we know that,

Moles of = Moles of AgCl = Moles of =

The formula of Douglasite is,

The molar mass of Douglasite = 311.88 g/mole

Now we have to calculate the moles of atoms.

In the formula of Douglasite, there are 4 atoms.

Now we have to calculate the mass of Douglasite.

conversion used : (1 g = 1000 mg)

Now we have to calculate the mass percent of Douglasite.

Therefore, the mass percent of Douglasite is 63.75 %

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