A sample of 7.52 grams of Na OH is dissolved into 675 mL of aqueous M NaOH (assume no volume change). This solution is then poured into 1.95 gallons of water. (You may assume that the two volumes can be added.) What is the concentration of NaOH in the final solution? Answer in units of M.
You omitted the molarity of the aqueous NaOH.
whoops..its 0.250 M NaOH
Convert 7.52 g NaOH to moles. moles = grams/molar mass.
Convert the solution to moles. moles = M x L.
Add the moles to find total moles and divide by total volume (in liters which means you must convert 1.95 gallons to liters).
To find the concentration of NaOH in the final solution, we need to calculate the number of moles of NaOH and then divide it by the total volume of the solution.
Step 1: Calculate the number of moles of NaOH.
To do this, we need to convert the mass of NaOH to moles. The molar mass of NaOH is 22.99 g/mol (sodium) + 16.00 g/mol (oxygen) + 1.01 g/mol (hydrogen) = 39.99 g/mol.
Number of moles = mass / molar mass
Number of moles = 7.52 g / 39.99 g/mol
Step 2: Convert the volume of the aqueous NaOH solution to liters.
Given volume = 675 mL = 0.675 L
Step 3: Calculate the concentration of NaOH in the aqueous solution.
Concentration (in M) = moles / volume
Concentration (in M) = (7.52 g / 39.99 g/mol) / 0.675 L
Step 4: Convert the volume of water in gallons to liters.
Given volume = 1.95 gallons
1 gallon = 3.78541 liters
Volume (in liters) = 1.95 gallons * 3.78541 liters/gallon
Step 5: Calculate the total volume of the solution.
Total volume = volume of aqueous NaOH solution + volume of water
Step 6: Calculate the concentration of NaOH in the final solution.
Concentration (in M) = moles / total volume
Now, let's calculate the concentration of NaOH in the final solution:
Concentration (in M) = (7.52 g / 39.99 g/mol) / ((0.675 L) + (1.95 gallons * 3.78541 liters/gallon))