Given the following equation:
2CH3CO2H + Ca(OH)2 --> Ca(CH3CO2)2 +H2O
If you start with 30 ml of a 5% solution of acetic acid, how much of a .1M Ca(OH)2 solution would it take to completely neutralize the acid?
I'm not quite sure how to start? Should I convert 30 ml to moles? and then use stoichiometry from the equation to convert it to Ca(OH)2?
Yes. Convert 5% soln to M then M x L = mols and use stoichiometry from there.
How would I convert 5% to M?
Is that 5% w/v; if so then it is 5g/100 mL soln. It may be easier to convert to grams. How many g acetic acid are in the 30 mL? That's 5.0 g x (30/100) = ?
Then mols acetic acid = ?/molar mass.
To solve this problem, you first need to calculate the moles of acetic acid in the given 30 ml of a 5% solution. Then, you can use stoichiometry to determine the amount of Ca(OH)2 required to neutralize the acid.
Here are the steps to follow:
Step 1: Convert the volume of the acetic acid solution (30 ml) to moles of acetic acid.
To do this, you'll need to know the molarity (M) of the acetic acid. The molarity can be calculated using the percent concentration:
Molarity (M) = percentage/100 * density/molar mass
Assuming the density of the acetic acid solution is equal to the density of water (1 g/ml), the molar mass of acetic acid (CH3CO2H) is approximately 60.05 g/mol, and the percentage is 5%, you can calculate the molarity of the acetic acid:
Molarity (M) = 5/100 * 1/60.05
Now, you can multiply the molarity by the volume in liters (30 ml = 0.03 L) to get the moles of acetic acid:
Moles of acetic acid = Molarity * Volume (in liters)
Step 2: Use stoichiometry to determine the moles of Ca(OH)2 needed to neutralize the acetic acid.
From the balanced equation, you can see that the stoichiometric ratio between acetic acid (CH3CO2H) and Ca(OH)2 is 2:1. It means that for every 2 moles of acetic acid, you'll need 1 mole of Ca(OH)2.
Moles of Ca(OH)2 = (Moles of acetic acid) / 2
Step 3: Convert the moles of Ca(OH)2 to the volume of the 0.1 M solution that would be required.
To convert moles to volume, you need to use the molarity (M) and the equation:
Moles = Molarity * Volume (in liters)
Rearranging the equation, you can solve for the volume:
Volume (in liters) = Moles / Molarity
Now, you can substitute the moles of Ca(OH)2 and the molarity (0.1 M) to calculate the volume:
Volume (in liters) = (Moles of Ca(OH)2) / 0.1
Finally, you can convert the volume back to milliliters (ml) if needed.
That's it! By following these steps, you can determine the amount of a 0.1 M Ca(OH)2 solution required to completely neutralize the given 30 ml of a 5% solution of acetic acid.