How many milliliters of 0.150M BaCl2 are needed to react completely with 40.0mL of 0.260M Na2SO4?
Na2SO4 + BaCl2 ==> BaSO4 + 2NaCl
mols Na2SO4 = M x L = ?
mols BaCl2 needed = same as mols Na2SO4 since the reaction coefficients are 1 mol Na2SO4 to 1 mol BaCl2.
Then M BaCl2 = mols BaCl2/L BaCl2. You know M and mols, solve for L and convert to mL.
To find the number of milliliters of 0.150M BaCl2 needed to react completely with 40.0mL of 0.260M Na2SO4, we need to use the stoichiometry of the balanced chemical equation for the reaction.
The balanced chemical equation for the reaction between BaCl2 and Na2SO4 is:
BaCl2 + Na2SO4 -> BaSO4 + 2NaCl
In this equation, we can see that one mole of BaCl2 reacts with one mole of Na2SO4 to form one mole of BaSO4 and two moles of NaCl.
First, we need to calculate the number of moles of Na2SO4 in 40.0mL of 0.260M solution. To do this, we use the formula:
moles = volume (in liters) × concentration (in moles per liter)
Given that the volume is 40.0mL (which is equivalent to 0.040L) and the concentration is 0.260M, we can calculate the number of moles of Na2SO4 as follows:
moles of Na2SO4 = 0.040L × 0.260M = 0.0104 moles
According to the balanced equation, one mole of BaCl2 reacts with one mole of Na2SO4. Therefore, the number of moles of BaCl2 needed to react completely with 0.0104 moles of Na2SO4 is also 0.0104 moles.
Finally, we need to determine the volume of 0.150M BaCl2 solution that contains 0.0104 moles. To find the volume, we rearrange the formula for moles:
moles = volume (in liters) × concentration (in moles per liter)
Rearranging: volume (in liters) = moles / concentration (in moles per liter)
Substituting the values, we get:
volume (in liters) = 0.0104 moles / 0.150M = 0.0693 L
Since the question asks for the volume in milliliters, we convert the volume from liters to milliliters:
volume (in milliliters) = 0.0693 L × 1000 = 69.3 mL
Therefore, 69.3 milliliters of 0.150M BaCl2 are needed to react completely with 40.0mL of 0.260M Na2SO4.