To solve this problem, we need to find the number of moles of chloride ions in the solution and then calculate the concentration.
Step 1: Find the number of moles of MgCl2 and NaCl.
- The molar mass of MgCl2 is 95.211 g/mol.
- The molar mass of NaCl is 58.443 g/mol.
Number of moles of MgCl2 = mass of MgCl2 / molar mass of MgCl2
= 20.0 g / 95.211 g/mol
= 0.210 moles
Number of moles of NaCl = mass of NaCl / molar mass of NaCl
= 20.0 g / 58.443 g/mol
= 0.342 moles
Step 2: Calculate the total number of moles of chloride ions.
- Each MgCl2 molecule contains 2 chloride ions.
- Each NaCl molecule contains 1 chloride ion.
Total number of chloride ions = (2 chloride ions/molecule * 0.210 moles of MgCl2) + (1 chloride ion/molecule * 0.342 moles of NaCl)
= 0.420 moles + 0.342 moles
= 0.762 moles
Step 3: Calculate the concentration of chloride ions.
Concentration = number of moles / volume of solution
= 0.762 moles / 2.00 dm^3
= 0.381 mol/dm^3
Therefore, the concentration of the chloride ions in the solution is 0.381 mol/dm^3.
20,0 g MgCl2 and 20.0 g NaCl are mixed together and dissolved in water to make up 2,00 dm^3 of solution. Calculate the concentration of the chloride ions in the solution. (0,381)
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