Calculate the mass of NaOH needed to prepare 100ml of 0.20molar solution.
B. Calculate the mass of solid KHP needed to react completely with 25ml of a 0.20m NaOH solution.
C. Calculate the molar amount of solid KHP used to neutralize the NaOH solution.
A. Calculate the mass of NaOH needed to prepare 100ml of 0.20 molar
solution.
mols NaOH needed = M x L = 0.20 x 0.1 = 0.020 mols.
grams = mols x molar mass = 0.020 x approx 40 = about 0.80 grams. I'm estimating so you must reconfirm all of these numbers.
B. Calculate the mass of solid KHP needed to react completely with 25ml of a 0.20m NaOH solution.
You MUST mean 0.20 M and not m. M stands for molarity; m stands for molality. NaOH + KHP ==> NaKP + H2O
mols NaOH = M x L = 0.20 x 0.025 = 0.005
The equation tells you that 1 mol NaOH reacts with 1 mol KHP; therefore, mols KHP reacted must be 0.005.
Then grams KHP = mols KHP x molar mass KHP = ?
C. Calculate the molar amount of solid KHP used to neutralize the NaOH solution.
I did that in part B above
Post your work if you have any questions.
A. To calculate the mass of NaOH needed to prepare a 0.20 molar solution in 100 ml, we will use the formula:
Molarity (M) = moles of solute / volume of solution (L)
First, convert the volume of solution from ml to L:
100 ml = 0.100 L
Rearrange the formula to solve for moles of solute:
moles of solute = Molarity (M) x volume of solution (L)
Substitute the given values:
Molarity (M) = 0.20 mol/L
Volume of solution (L) = 0.100 L
moles of solute = 0.20 mol/L x 0.100 L
moles of solute = 0.020 mol
The molar mass of NaOH is:
Na = 22.99 g/mol
O = 16.00 g/mol
H = 1.01 g/mol
Molar mass of NaOH = 22.99 g/mol + 16.00 g/mol + 1.01 g/mol
Molar mass of NaOH = 39.00 g/mol
To calculate the mass of NaOH needed, multiply the moles of NaOH by the molar mass:
Mass of NaOH = moles of solute x molar mass of NaOH
Mass of NaOH = 0.020 mol x 39.00 g/mol
Mass of NaOH = 0.78 grams
Therefore, the mass of NaOH needed to prepare a 0.20 molar solution in 100 ml is 0.78 grams.
B. To determine the mass of solid KHP needed to react completely with 25 ml of 0.20 M NaOH solution, we need to use the stoichiometry of the reaction between KHP (Potassium Hydrogen Phthalate) and NaOH.
The balanced chemical equation for the reaction is:
KHP + NaOH → NaKP + H2O
From the balanced equation, we can see that the molar ratio between KHP and NaOH is 1:1.
First, calculate the moles of NaOH we have:
moles of NaOH = Molarity (M) x volume of solution (L)
moles of NaOH = 0.20 mol/L x 0.025 L
moles of NaOH = 0.005 mol
Since the molar ratio between KHP and NaOH is 1:1, the moles of KHP needed will also be 0.005 mol.
Next, we need to find the molar mass of KHP:
K = 39.10 g/mol
H = 1.01 g/mol
P = 31.00 g/mol
Molar mass of KHP = 39.10 g/mol + 1.01 g/mol + 31.00 g/mol
Molar mass of KHP = 71.11 g/mol
To calculate the mass of KHP needed, multiply the moles of KHP by the molar mass:
Mass of KHP = moles of KHP x molar mass of KHP
Mass of KHP = 0.005 mol x 71.11 g/mol
Mass of KHP = 0.36 grams
Therefore, the mass of solid KHP needed to react completely with 25 ml of 0.20 M NaOH solution is 0.36 grams.
C. To calculate the molar amount of solid KHP used to neutralize the NaOH solution, we can use the same approach from part B.
The molar mass of KHP is 71.11 g/mol, and the mass of KHP used is 0.36 grams.
To calculate the moles of KHP used, divide the mass of KHP by its molar mass:
moles of KHP = mass of KHP / molar mass of KHP
moles of KHP = 0.36 g / 71.11 g/mol
moles of KHP ≈ 0.005 mol
Therefore, the molar amount of solid KHP used to neutralize the NaOH solution is approximately 0.005 mol.
To solve these questions, we need to use the concept of molarity and mole-to-mole ratios. Let's go step by step.
A. Calculate the mass of NaOH needed to prepare 100ml of 0.20 molar solution:
Step 1: Write down the given information:
- Volume of the solution (V) = 100 ml = 0.1 L
- Molarity (M) = 0.20 M
Step 2: Recall the formula for molarity:
Molarity (M) = moles of solute / volume of solution in liters
Step 3: Rearrange the formula to solve for moles of solute:
moles of solute = Molarity (M) x Volume of solution (V)
Step 4: Calculate the moles of NaOH:
moles of NaOH = 0.20 M x 0.1 L = 0.02 moles
Step 5: Determine the molar mass of NaOH:
Molar mass of NaOH = 22.99 g/mol + 16.00 g/mol + 1.01 g/mol = 39.99 g/mol
Step 6: Calculate the mass of NaOH:
Mass of NaOH = moles of NaOH x molar mass of NaOH
Mass of NaOH = 0.02 moles x 39.99 g/mol = 0.7998 g
Therefore, the mass of NaOH needed to prepare 100 ml of 0.20 molar solution is approximately 0.7998 grams.
B. Calculate the mass of solid KHP needed to react completely with 25 ml of a 0.20 M NaOH solution:
Step 1: Write down the given information:
- Volume of NaOH solution (V) = 25 ml = 0.025 L
- Molarity of NaOH (M) = 0.20 M
- Balanced chemical equation:
KHP (potassium hydrogen phthalate) + NaOH -> NaKHP + H2O
Step 2: Determine the moles of NaOH:
moles of NaOH = Molarity (M) x Volume of solution (V)
moles of NaOH = 0.20 M x 0.025 L = 0.005 moles
Step 3: Use the mole-to-mole ratio from the balanced chemical equation to determine the moles of KHP:
From the balanced chemical equation:
1 mol KHP reacts with 1 mol NaOH
Since the mole ratio is 1:1, the moles of KHP will be the same as the moles of NaOH.
Step 4: Determine the molar mass of KHP:
Molar mass of KHP = 204.22 g/mol
Step 5: Calculate the mass of KHP:
Mass of KHP = moles of KHP x molar mass of KHP
Mass of KHP = 0.005 moles x 204.22 g/mol = 1.0211 g
Therefore, the mass of solid KHP needed to react completely with 25 ml of a 0.20 M NaOH solution is approximately 1.0211 grams.
C. Calculate the molar amount of solid KHP used to neutralize the NaOH solution:
Since the mole ratio of NaOH to KHP from the balanced chemical equation is 1:1, the molar amount of solid KHP used to neutralize the NaOH solution is also 0.005 moles.