How will you prepare 500ml of 16%equeous ethanol(46.1g/mol)
16% w/v means 16 g ethanol in 100 mL solution. So add 5*16 = 80 g ethanol, place in a 500 mL volumetric flask, and make to the mark with distilled water.
To prepare 500ml of a 16% aqueous ethanol solution, you will first need to calculate the amount of ethanol and water required.
Step 1: Calculate the volume of ethanol required.
We can use the formula:
Volume of ethanol (ml) = Volume of solution (ml) × Percentage of ethanol/100
Volume of ethanol = 500ml × 16/100
Volume of ethanol = 80ml
Step 2: Calculate the mass of ethanol required.
To calculate the mass of ethanol, we can use the formula:
Mass of ethanol (g) = Volume of ethanol (ml) × Density of ethanol (g/ml)
The density of ethanol is approximately 0.789 g/ml.
Mass of ethanol = 80ml × 0.789 g/ml
Mass of ethanol = 63.12g
Step 3: Calculate the mass of water required.
To find the mass of water, we need to subtract the mass of ethanol from the total mass of the solution.
Mass of water = Mass of solution - Mass of ethanol
Mass of water = (500g - 63.12g)
Mass of water = 436.88g
So, to prepare 500ml of a 16% aqueous ethanol solution, you will need 63.12g of ethanol and 436.88g of water.