Determine the quantity (g) of pure CaCl2 in 7.5 g of CaCl2•9H2O.
Well, interestingly enough, the chemical formula CaCl2•9H2O means that there are 9 molecules of water (H2O) that are bound to one molecule of CaCl2.
Given that the molar mass of CaCl2 is about 111 g/mol and the molar mass of H2O is about 18 g/mol, we can calculate the molar mass of CaCl2•9H2O:
(1 mol CaCl2) + (9 mol H2O) = 111 g/mol + 9 * 18 g/mol = 207 g/mol.
Now, to determine the quantity of pure CaCl2 in 7.5 g of CaCl2•9H2O, we can set up a simple proportion:
(7.5 g CaCl2•9H2O) / (207 g CaCl2•9H2O) = (x g CaCl2) / (111 g CaCl2),
where x is the quantity of pure CaCl2 we want to determine.
Solving for x, we find:
x = (7.5 g CaCl2•9H2O) * (111 g CaCl2) / (207 g CaCl2•9H2O) ≈ 4.02 g.
So, the quantity of pure CaCl2 in 7.5 g of CaCl2•9H2O is approximately 4.02 g.
But hey, don't be salty about it! Calcium chloride is here to make your equations all ion-teresting!
To determine the quantity of pure CaCl2 in 7.5 g of CaCl2•9H2O, we need to account for the molar mass and the stoichiometry of the compound.
Step 1: Calculate the molar mass of CaCl2•9H2O:
- The molar mass of CaCl2 is 40.08 g/mol (calcium: 40.08 g/mol + chlorine: 35.45 g/mol + chlorine: 35.45 g/mol).
- The molar mass of 9H2O is 162.27 g/mol (hydrogen: 1.01 g/mol x 18 atoms + oxygen: 16.00 g/mol x 9 atoms).
CaCl2•9H2O = 40.08 g/mol + 162.27 g/mol = 202.35 g/mol
Step 2: Calculate the number of moles of CaCl2•9H2O in 7.5 g:
- Using the molar mass calculated earlier:
Number of moles = mass / molar mass
Number of moles = 7.5 g / 202.35 g/mol
Step 3: Determine the stoichiometry of CaCl2 in CaCl2•9H2O:
- The molar ratio of CaCl2 to CaCl2•9H2O is 1:1.
Step 4: Calculate the molar mass of pure CaCl2:
- The molar mass of CaCl2 is 40.08 g/mol.
Step 5: Calculate the quantity of pure CaCl2 in 7.5 g of CaCl2•9H2O:
- The number of moles of CaCl2 is the same as the number of moles of CaCl2•9H2O, as they have a 1:1 stoichiometric ratio.
- Therefore, the mass of pure CaCl2 is:
Mass = number of moles x molar mass
Mass = number of moles x 40.08 g/mol
You can substitute the value for the number of moles you obtained from Step 2 into the equation to find the mass of pure CaCl2 in grams.
To determine the quantity of pure CaCl2 in 7.5 g of CaCl2•9H2O, we need to account for the water molecules present in the compound and calculate the mass of pure CaCl2.
CaCl2•9H2O means that there are 9 water molecules bonded to each calcium chloride molecule. The molar mass of CaCl2 is 110.98 g/mol, and the molar mass of H2O is 18.02 g/mol.
Step 1: Calculate the molar mass of CaCl2•9H2O:
The molar mass of CaCl2 is 110.98 g/mol.
The molar mass of H2O is 18.02 g/mol.
Since there are 9 water molecules, we multiply the molar mass of H2O by 9: 18.02 g/mol × 9 = 162.18 g/mol.
Now, add the molar masses of CaCl2 and 9H2O: 110.98 g/mol + 162.18 g/mol = 273.16 g/mol.
Step 2: Calculate the amount (in moles) of CaCl2•9H2O:
To calculate the number of moles, divide the mass of CaCl2•9H2O by its molar mass.
7.5 g ÷ 273.16 g/mol = 0.027 moles.
Step 3: Determine the quantity (in g) of pure CaCl2:
Since the molar ratio between CaCl2 and CaCl2•9H2O is 1:1, the amount of pure CaCl2 is the same as the amount of CaCl2•9H2O.
0.027 moles × 110.98 g/mol = 3.00 g.
Therefore, there is 3.00 g of pure CaCl2 in 7.5 g of CaCl2•9H2O.