8.00g of NaOH are dissolved in water to make 4.00L of solution. What is the concentration of hydronium ions, [H3O+], in this solution?
Express your answer with the appropriate units.
To find the concentration of hydronium ions, [H3O+], in a solution, we need to use the concept of molarity. Molarity is defined as the number of moles of solute per liter of solution.
First, we need to determine the number of moles of NaOH present in the solution. The molar mass of NaOH is 22.99 g/mol for Na, plus 16.00 g/mol for O, and 1.01 g/mol for H. Therefore, the molar mass of NaOH is 22.99 + 16.00 + 1.01 = 39.00 g/mol.
To find the number of moles, we divide the given mass by the molar mass:
moles of NaOH = mass of NaOH / molar mass of NaOH
moles of NaOH = 8.00 g / 39.00 g/mol
moles of NaOH = 0.205 moles
Next, we need to find the volume of the solution in liters. We are given that the solution has a volume of 4.00 L.
Now we can calculate the molarity (M) of the solution using the formula:
Molarity (M) = moles of solute / volume of solution (in L)
Molarity (M) = 0.205 moles / 4.00 L
Molarity (M) = 0.0513 M
Since we need to find the concentration of hydronium ions, [H3O+], in the solution, we assume that the NaOH fully dissociates in water to give one Na+ ion and one OH- ion. Hence, the concentration of hydronium ions ([H3O+]) is equal to the concentration of hydroxide ions ([OH-]) in the solution.
Therefore, the concentration of hydronium ions, [H3O+], in this solution is 0.0513 M.
To determine the concentration of hydronium ions, [H3O+], in the solution, we need to use the concept of molarity.
We are given:
- Mass of NaOH: 8.00 g
- Volume of solution: 4.00 L
First, we need to calculate the number of moles of NaOH:
Moles of NaOH = Mass of NaOH / Molar mass of NaOH
The molar mass of NaOH is calculated as follows:
Na (22.99 g/mol) + O (16.00 g/mol) + H (1.01 g/mol) = 39.99 g/mol
Moles of NaOH = 8.00 g / 39.99 g/mol ≈ 0.200 moles
Next, we calculate the molarity of the NaOH solution:
Molarity = Moles of solute / Volume of solution
Moles of solute = Moles of NaOH = 0.200 moles
Volume of solution = 4.00 L
Molarity = 0.200 moles / 4.00 L ≈ 0.050 M
Since NaOH is a strong base that dissociates completely in water, we know that in solution, each NaOH molecule produces one hydronium ion, H3O+. Therefore, the concentration of hydronium ions, [H3O+], is equal to the molarity of the NaOH solution.
Therefore, the concentration of hydronium ions in the solution is approximately 0.050 M.
mols NaOH = grams/molar mass = ?
M NaOH = mols NaOH/L solution
(OH^-) = (NaOH)
Then (H3O^+)(OH^-) = Kw = 1E-14
Solve for (H3O^+).