what is the pH of solution made by mixing 100 mL of 0.030M HCL with 200 mL water?
(HCl) = 0.030M x (300/100) = ?
Note this assumes that the volumes are additive. Technically they are not.
pH = -log(HCl) = ?
To find the pH of the solution made by mixing HCl with water, we need to use some basic concepts of chemistry.
Step 1: Find the moles of HCl used
To calculate the moles of HCl, we use the equation:
moles = (concentration in M) x (volume in liters)
Given that the concentration of HCl is 0.030 M and the volume used is 100 mL (0.100 L):
moles of HCl = 0.030 M × 0.100 L = 0.003 moles
Step 2: Calculate the total volume of the solution
Since the HCl is mixed with 200 mL (0.200 L) of water, the total volume of the solution is 0.100 L + 0.200 L = 0.300 L.
Step 3: Calculate the final concentration of HCl in the solution
To determine the final concentration of HCl in the solution, we divide the moles of HCl by the total volume of the solution:
final concentration = (moles of HCl) / (total volume of the solution)
final concentration = 0.003 moles / 0.300 L = 0.010 M
Step 4: Calculate the pH of the solution
The pH of a solution can be determined using the formula:
pH = -log[H+]
The [H+] is the concentration of the hydrogen ions in the solution. In this case, because HCl is a strong acid, it disassociates completely into H+ ions and Cl- ions. Therefore, the concentration of H+ ions is equal to the concentration of HCl.
pH = -log(0.010 M) = -(-1) = 1
So, the pH of the solution made by mixing 100 mL of 0.030 M HCl with 200 mL of water is 1.