calculate the molarity of 30.0g of NaOH in 350. mL of NaOH solution
To calculate the molarity of a solution, you need to know the moles of solute and the volume of the solution in liters.
Step 1: Convert the mass of NaOH to moles.
To convert grams to moles, you need to divide the mass by the molar mass of NaOH. The molar mass of NaOH is the sum of the atomic masses of sodium (Na), oxygen (O), and hydrogen (H).
The atomic masses are:
- Sodium (Na) = 22.99 g/mol
- Oxygen (O) = 16.00 g/mol
- Hydrogen (H) = 1.01 g/mol
Molar mass of NaOH = (22.99 g/mol) + (16.00 g/mol) + (1.01 g/mol) = 39.00 g/mol
Moles of NaOH = mass of NaOH / molar mass of NaOH
Moles of NaOH = 30.0 g / 39.00 g/mol
Step 2: Convert the volume of the solution to liters.
The given volume is in milliliters, so we need to convert it to liters. Since 1 L = 1000 mL, you divide the volume by 1000 to convert it.
Volume of NaOH solution in liters = 350 mL / 1000 mL/L
Step 3: Calculate the molarity.
Molarity (M) is defined as moles of solute divided by the volume of the solution in liters.
Molarity (M) = moles of NaOH / volume of NaOH solution (in liters)
Substitute the values into the formula:
Molarity (M) = (moles of NaOH) / (volume of NaOH solution in liters)
Now, you can calculate the molarity.
To calculate the molarity (M) of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters).
First, let's find the number of moles of NaOH:
Step 1: Convert the mass of NaOH to moles.
The molar mass of NaOH (sodium hydroxide) is:
Na: 22.99 g/mol
O: 16.00 g/mol
H: 1.01 g/mol
Molar mass of NaOH = 22.99 + 16.00 + 1.01 = 40.00 g/mol
To find the moles, use the formula:
moles = mass / molar mass
moles = 30.0 g / 40.00 g/mol
moles = 0.75 mol
Step 2: Convert the volume of the solution to liters.
350. mL = 350. mL * (1 L / 1000 mL)
350. mL = 0.350 L
Step 3: Calculate the molarity (M).
Molarity = moles / volume
Molarity = 0.75 mol / 0.350 L
Molarity = 2.14 M
Therefore, the molarity of the NaOH solution is 2.14 M.
M = moles/L
mols = grams/molar mass.