Neutralization Reaction Molarity Calculations:
For example: What is the molarity of a Ca(OH)2 solution if .032 L of the solution is exactly neutralized by .015 of a 0.56 M HCl?
How do I solve- I am unsure where to begin.
Balance the equation:
Ca(OH)2 + 2HCl >> CaCl2 + 2H20
ok, it takes two moles of HCl for each mole of Calcium hydroxide.
moles Ca(OH)=Molarity*volume and you don't know M
moles HCl= molarity*Volume=.56*.015
so, the 2* molesCa(OH)2= moleHCL
and you can then find molarity of the calcium hydroxide.
Thanks!
To solve this problem, you can use the concept of molarity (M) and the balanced chemical equation of the neutralization reaction. Molarity is defined as the number of moles of solute in one liter of solution.
Here's how you can approach the problem step-by-step:
Step 1: Write the balanced chemical equation for the neutralization reaction. In this case, the neutralization reaction can be represented as:
Ca(OH)2 + 2HCl -> CaCl2 + 2H2O
Step 2: Determine the stoichiometry of the reaction. According to the balanced chemical equation, one mole of Ca(OH)2 reacts with two moles of HCl to produce one mole of CaCl2 and two moles of water.
Step 3: Calculate the number of moles of HCl used in the reaction. You can do this by using the formula:
moles of solute = molarity × volume
Given that the volume of the HCl solution is 0.015 L and the concentration is 0.56 M, you can calculate the number of moles as follows:
moles of HCl = 0.56 M × 0.015 L = 0.0084 moles of HCl
Step 4: Determine the stoichiometric ratio between HCl and Ca(OH)2. From the balanced equation, you can see that two moles of HCl react with one mole of Ca(OH)2. Therefore, to neutralize the calculated moles of HCl, we need half of that amount in moles of Ca(OH)2.
moles of Ca(OH)2 = 0.0084 moles of HCl / 2 = 0.0042 moles of Ca(OH)2
Step 5: Calculate the molarity of the Ca(OH)2 solution by dividing the moles of Ca(OH)2 by the volume of the solution. Given that the volume of the Ca(OH)2 solution is 0.032 L, you can calculate the molarity as:
molarity of Ca(OH)2 = moles of Ca(OH)2 / volume of solution
= 0.0042 moles / 0.032 L
= 0.13125 M (rounded to four decimal places)
Therefore, the molarity of the Ca(OH)2 solution is approximately 0.1313 M.
Remember to always double-check your calculations and pay attention to units to ensure accurate results.