Suppose your teacher ask you to prepare 250cm³ of 1 Mol dm -³ (1M) of sodium hydroxide for chemistry lesson . How would prepare this solution?
I'm not sure this will help but this is all I know. (Sorry)
To make 1 M NaOH solution, you have to dissolve 40.00 g of sodium hydroxide pellets in 250 mL distilled water and then make up the solution to 1 liter. Weigh 19.95 gm of NaOH pellets & dissolve them in half liter(500ml) of distilled water water, what you will be having now is 1M NaOH solution.
Good luck!
All of what This8thGradeGirl0_0 says is correct except that it doesn't answer the question. Yes, 40 g NaOH pellets dissolved in 1 L of solution is 1 M. The question asks however, for the preparation of 250 cc of 1M. Therefore, dissolve 40/4 = 10 g NaOH pellets in some water, make to a fiinal volume of 250 cc and mix thoroughly. That is 1 M also. I should point out that such a solution will be close to 1 M but probably not 1 M BECAUSE NaOH pellets are hygroscopic (they pick up water from the atmosphere) so when you weigh out 10 g NaOH is isn't pure NaOH; i.e., it is mostly NaOH but you're weighing out some wate with it too.
To prepare 250 cm³ of 1M sodium hydroxide (NaOH) solution, you will need to follow these steps:
Step 1: Determine the molar mass of sodium hydroxide (NaOH). The molar mass of NaOH is calculated by adding the atomic masses of sodium (Na) and oxygen (O), then adding the atomic mass of hydrogen (H). The atomic masses are: Na = 23 g/mol, O = 16 g/mol, and H = 1 g/mol. So the molar mass of NaOH is 23 + 16 + 1 = 40 g/mol.
Step 2: Calculate the number of moles of NaOH required. Since the desired concentration of the solution is 1M, and the volume is given as 250 cm³, we can use the formula:
Moles = Concentration x Volume
Moles = 1 M x 0.250 dm³ (since 1 dm³ = 1000 cm³)
Moles = 0.250 mol
Step 3: Calculate the mass of NaOH required using the number of moles and molar mass. Since we know the number of moles from the previous step and the molar mass of NaOH, we can use the formula:
Mass = Moles x Molar Mass
Mass = 0.250 mol x 40 g/mol
Mass = 10 g
So, you will need 10 grams of sodium hydroxide to prepare 250 cm³ of 1M NaOH solution.
Step 4: Measure out 10 grams of solid NaOH. It's important to use the correct weighing technique and equipment for precise and accurate measurements.
Step 5: Add the measured amount of NaOH to a clean, dry beaker.
Step 6: Add distilled water slowly in small increments to dissolve the NaOH. Ensure the NaOH is fully dissolved.
Step 7: Once the NaOH is completely dissolved, transfer the solution into a volumetric flask or container with a volume of 250 cm³.
Step 8: Add distilled water to the flask to reach the 250 cm³ mark. It's important to add the water carefully to avoid air bubbles and ensure accurate volume measurement.
Step 9: Mix the solution gently by swirling the flask to ensure even distribution.
You have now successfully prepared 250 cm³ of 1M sodium hydroxide solution. Remember to label the container properly and follow appropriate safety precautions while handling chemicals.
To prepare a 1M solution of sodium hydroxide (NaOH) with a volume of 250cm³, you need to follow these steps:
1. Determine the molar mass of NaOH: The molar mass of sodium (Na) is approximately 23g/mol, oxygen (O) is approximately 16g/mol, and hydrogen (H) is approximately 1g/mol. Adding these together, we get:
- Na: 1 atom x 23g/mol = 23g/mol
- O: 1 atom x 16g/mol = 16g/mol
- H: 1 atom x 1g/mol = 1g/mol
Total: 40g/mol
2. Calculate the amount of NaOH needed: Since we want 1 mol of NaOH to be dissolved in 1 liter (1000cm³) of water, we need to calculate the number of moles for our desired volume of 250cm³. Using the formula:
- Moles = Volume (in liters) x Concentration (in mol/dm³)
Since the concentration is 1M, we can substitute:
- Moles = 250cm³ / 1000cm³/L x 1 mol/dm³ = 0.25 mol
3. Determine the mass of NaOH needed: To find the mass of NaOH required, we multiply the number of moles by the molar mass of NaOH:
- Mass = Number of Moles x Molar Mass
- Mass = 0.25 mol x 40g/mol = 10g
So, to prepare 250cm³ of 1M NaOH solution, you would need to dissolve 10g of NaOH in enough water to make a final volume of 250cm³.