A .600 g sample of CaCO3 is disolve in concentrated HCl (12M). the solution was diluted to 250 mL in a volumetric flask to obtain a solution for standardizing the EDTA titrant.
1 What is the molarity of the Ca2+ (calcium ion) in the flask?
2 How many moles of Ca2+ are in a 25 mL aliquot of the solution in question 1?
So you have 0.600 g in 250 mL. That is 0.600/100 = 0.006 moles CaCO3. (I estimated the molar mass CaCO3; you need to confirm and update it.)
Molarity = moles/L = moles/0.250 L = ?
How many moles do you have in the 250. How many moles in 1/10th that?
yes the calcium carbonate has (MW= 100.09 g)hence the moles for CaCo3 is correct but how do you calculate the mole for calcium ion Ca2+
Don't you have 1 Ca^+2 ion for every mole CaCO3 there?
Let me redo that. Don't you have 1 atom Ca^+2 for every molecule CaCO3; done another way, don't you have 1 mole Ca^+2 for every mole CaCO3?
2HCl+CaCO3=CaCl2 + H2O + CO2... i think so....
I don't know why you need an equation. There is 1 mole of Ca +2 ions in every mole of CaCO3; therefore, the concn of CaCO3 and the concn of Ca +2 ion are the same. For that matter, C ion is the and CO3 ion is the same as CaCO3. The oxygen concn (although not there as a gas) is 3 times that.
To find the molarity of the Ca2+ ions in the flask, we need to understand the reaction that takes place between CaCO3 and HCl. The reaction is as follows:
CaCO3 + 2HCl -> CaCl2 + CO2 + H2O
From the balanced equation, we can see that 1 mole of CaCO3 reacts with 2 moles of HCl to produce 1 mole of CaCl2.
To calculate the molarity (M) of Ca2+ in the flask, we need to determine the number of moles of CaCl2 formed. The molarity is defined as moles of solute divided by the volume of solution in liters.
Step 1: Calculate the number of moles of CaCO3 used:
molar mass of CaCO3 = 40.08 g/mol + 12.01 g/mol + (3 x 16.00 g/mol) = 100.09 g/mol
moles of CaCO3 = mass / molar mass = 0.600 g / 100.09 g/mol = 0.005997 moles
Step 2: Calculate the number of moles of CaCl2 formed:
from the balanced equation, we know that 1 mole of CaCO3 reacts to produce 1 mole of CaCl2.
Therefore, the number of moles of CaCl2 formed is also 0.005997 moles.
Step 3: Calculate the volume of the solution in liters:
volume of solution = 250 mL = 0.250 L
Step 4: Calculate the molarity of Ca2+ ions:
Molarity (M) = moles of solute / volume of solution in liters
Molarity of Ca2+ = 0.005997 moles / 0.250 L = 0.024 M
Therefore, the molarity of Ca2+ ions in the flask is 0.024 M.
To calculate the number of moles of Ca2+ in a 25 mL aliquot of the solution, we can use the molarity and the volume of the aliquot.
Step 5: Calculate the number of moles of Ca2+ in the 25 mL aliquot:
moles of Ca2+ = Molarity x Volume (in liters)
moles of Ca2+ = 0.024 M x 0.025 L = 0.0006 moles
Therefore, there are 0.0006 moles of Ca2+ in the 25 mL aliquot of the solution from question 1.