1. what mass of sodium hydroxide is required to make up 100 mL of 0.5000M solution
2.What volume of this solution must be diluted down to 100 mL if 0.100M solution of NaOH is required?
1.
How many moles do you need? That's mols = M x L = ?
Then convert to grams. mols = g/molar mass. You know mols and molar mass, solve for grams.
2. Use the dilution formula.
mL1 x M1 = mL2 x M2
mL1 x 0.5 = 100 x 0.1
Solve f r mL1.
1. To determine the mass of sodium hydroxide required to make up a 100 mL 0.5000 M solution, we need to know the molar mass of NaOH.
The molar mass of sodium (Na) is approximately 22.99 g/mol, the molar mass of oxygen (O) is approximately 16.00 g/mol, and the molar mass of hydrogen (H) is approximately 1.01 g/mol.
The molar mass of NaOH can be calculated by adding the molar masses of each element:
Molar mass of NaOH = (mass of Na) + (mass of O) + (mass of H)
= (22.99 g/mol) + (16.00 g/mol) + (1.01 g/mol)
= 40.00 g/mol
To calculate the mass of sodium hydroxide required, we can use the equation:
Mass (g) = Volume (L) x Concentration (mol/L) x Molar mass (g/mol)
Given:
Volume = 100 mL = 0.100 L
Concentration = 0.5000 M
Molar mass of NaOH = 40.00 g/mol
Mass (g) = 0.100 L x 0.5000 mol/L x 40.00 g/mol
= 2.00 g
Therefore, 2.00 grams of sodium hydroxide is required to make up 100 mL of 0.5000 M solution.
2. To determine the volume of the solution that must be diluted down to 100 mL to create a 0.100 M solution, we can use the equation:
Concentration1 x Volume1 = Concentration2 x Volume2
Given:
Concentration1 = 0.5000 M
Volume1 = ?
Concentration2 = 0.100 M
Volume2 = 100 mL = 0.100 L
Using the equation above, we can solve for Volume1:
0.5000 M x Volume1 = 0.100 M x 0.100 L
Volume1 = (0.100 M x 0.100 L) / 0.5000 M
Volume1 = 0.020 L
Therefore, 0.020 L or 20 mL of the 0.5000 M solution must be diluted down to 100 mL in order to create a 0.100 M solution of NaOH.
To calculate the mass of sodium hydroxide (NaOH) required to make a 0.5000M solution in 100 mL:
Step 1: Convert the desired volume (100 mL) to liters by dividing by 1000:
Volume (L) = 100 mL ÷ 1000 = 0.1 L
Step 2: Use the formula for calculating the number of moles:
Moles = concentration (M) × volume (L)
Moles = 0.5000M × 0.1 L = 0.0500 moles
Step 3: Convert moles of NaOH to grams using the molar mass of NaOH. The molar mass of NaOH is calculated by adding the atomic masses of sodium (Na), oxygen (O), and hydrogen (H).
Molar mass of Na = 22.99 g/mol
Molar mass of O = 16.00 g/mol
Molar mass of H = 1.01 g/mol
Sum = 22.99 + 16.00 + 1.01 = 40.00 g/mol
Mass (g) = Moles × Molar mass
Mass (g) = 0.0500 moles × 40.00 g/mol = 2.00 grams
Therefore, 2.00 grams of sodium hydroxide (NaOH) is required to make 100 mL of 0.5000M solution.
For the second question, to find the volume of the 0.5000M NaOH solution that needs to be diluted to obtain a 0.100M solution in a final volume of 100 mL:
Step 1: Use the formula for dilution:
C1 × V1 = C2 × V2
Where:
C1 = initial concentration (0.5000M)
V1 = initial volume to be diluted (unknown)
C2 = final concentration (0.100M)
V2 = final volume (100 mL)
Step 2: Rearrange the formula to solve for the initial volume (V1):
V1 = (C2 × V2) / C1
V1 = (0.100M × 100 mL) / 0.5000M
V1 = 20 mL
Therefore, to obtain a 0.100M NaOH solution in a final volume of 100 mL, you would need to dilute 20 mL of the 0.5000M NaOH solution with enough solvent to make a total of 100 mL.