strontium chloride can be obtained as the anhydrous salt, SrCl2, and as the hydrates SrCl2.2H20, and SrCl2.6H20. (ArSr = 87.5). 0.323 g of a sample of strontium chloride is dissolved in water and reacted with sliver nitrate solution. The mass of sliver chloride precipitates is 0.476 g. What is the formula of the strontium chloride? ( calulate the amount of the sliver chloride. Since 1 mol of sliver chloride contains 1 mol of chlorine as Cl-, from this you can calulate the mass of the chlorine in the 0.323 g of the strontium chloride.
0.323 g SrCl2.xH2O - g SrCl2 = g H2O.
How much SrCl2 is in the sample.
0.476 g AgCl x (1 mol SrCl2)/2 mol AgCl = ?? g SrCl2.
0.323 - ?? g SrCl2 = xx g H2O
mols SrCl2 = ??g SrCl2/molar mass SrCl2
mols H2O = xx g H2O/molar mass H2O
Find mols H2O per 1 mol SrCl2 and that will be x in the formula SrCl2*xH2O.
Post your work if you get stuck.
To find the formula of the strontium chloride, we need to determine the amount of chlorine in the given sample and then relate it to the amount of strontium chloride in the sample.
1. Calculate the amount of chlorine in the 0.323 g of strontium chloride:
- Since 1 mole of silver chloride (AgCl) contains 1 mole of chlorine (Cl-), we will use the equation:
0.476 g AgCl * (1 mol SrCl2/2 mol AgCl) = ?? g SrCl2
The molar mass of SrCl2 is determined by adding the atomic masses of strontium (Sr) and chlorine (Cl) present in one molecule:
Molar mass of SrCl2 = Atomic mass of Sr + (2 * Atomic mass of Cl)
2. Determine the mass of water (H2O) in the sample:
- We know that when strontium chloride dissolves in water, a certain amount of water molecules get incorporated into the crystal lattice. To calculate the mass of water, we use the equation:
0.323 g SrCl2 - ?? g SrCl2 = xx g H2O
Here, ?? g SrCl2 is the mass of strontium chloride calculated in step 1.
3. Calculate the number of moles of SrCl2 and H2O:
- Use the molar mass of SrCl2 and H2O to find the number of moles of each:
Moles of SrCl2 = ?? g SrCl2 / molar mass of SrCl2
Moles of H2O = xx g H2O / molar mass of H2O
4. Find the ratio of moles of H2O to 1 mole of SrCl2:
- Divide the number of moles of H2O by the number of moles of SrCl2 obtained in step 3. This ratio represents the value of x in the formula SrCl2*xH2O.
By following these steps, you should be able to determine the formula of the strontium chloride. If you encounter any issues or need further assistance, feel free to share your work, and I'll be happy to assist you.