How would you prepare 455 g of aqueous solution that is 6.50% sodium sulfate Na2SO4 by mass?
percent by mass = grams/100 g solution.
X grams/455 = 0.065
solve for X. Subtract 455-X to calculate how much water must be added.
check my thinking. Check my work.
To prepare a 6.50% sodium sulfate (Na2SO4) solution with a mass of 455 g, you need to follow these steps:
Step 1: Understand the problem.
The problem states that you need to prepare a solution that is 6.50% sodium sulfate by mass. This means that for every 100 g of solution, 6.50 g of it is sodium sulfate.
Step 2: Determine the amount of sodium sulfate needed.
To find the amount of sodium sulfate needed, you need to calculate 6.50% of the total mass of the solution. Multiply 455 g by 6.50% (or 0.065) to get the mass of sodium sulfate required.
Mass of sodium sulfate = 455 g * 0.065 = 29.575 g
So you need around 29.575 g of sodium sulfate.
Step 3: Calculate the amount of water needed.
To calculate the amount of water needed, subtract the mass of sodium sulfate from the total mass of the solution.
Mass of water = 455 g - 29.575 g = 425.425 g
Therefore, you would need around 425.425 g of water.
Step 4: Mix the sodium sulfate and water.
To prepare the solution, weigh out approximately 29.575 g of sodium sulfate and dissolve it in approximately 425.425 g of water. Stir the mixture thoroughly until the sodium sulfate is completely dissolved.
This will give you a 455 g aqueous solution that is approximately 6.50% sodium sulfate by mass.