What weight of potassium bromide, KBr, could be recovered by evaporating 650.0 g of 15.0 percent KBr solution to dryness?
15% KBr (w/w) means 15 g KBr/100 g soln. So how many grams KBr will you find in 650 g? That will be 15 x 650/100 = ? That's how much you can obtain by evaporation assuming good lab technique.
Well, let's try not to get in a "pickle" with this question. To find out the weight of potassium bromide that could be recovered, we first need to calculate the weight of KBr in the solution.
If the solution is 15.0% KBr, that means that 100 grams of the solution contains 15 grams of KBr. So in 650.0 grams of the solution, we would have 650.0 * (15 / 100) grams of KBr.
After some mathematical mischief, we find that the weight of KBr that could be recovered is approximately 97.5 grams. So if you're planning on evaporating this solution, be careful not to turn into a "salt bae" in the process!
To solve this problem, we need to find the weight of potassium bromide (KBr) present in the 15.0% solution.
Step 1: Convert the percentage to a decimal by dividing it by 100.
15.0% = 15.0/100 = 0.150
Step 2: Calculate the weight of KBr in the solution.
Weight of KBr = Percentage of KBr x Total weight of the solution
Weight of KBr = 0.150 x 650.0 g
Weight of KBr = 97.5 g
Therefore, if the 15.0% KBr solution is evaporated to dryness, you will be able to recover 97.5 grams of KBr.
To find the weight of potassium bromide (KBr) that could be recovered by evaporating 650.0 g of a 15.0 percent KBr solution to dryness, you need to follow these steps:
Step 1: Determine the mass of the KBr in the solution.
The solution is 15.0% KBr, which means that 15.0% of the solution's mass is KBr. To find the mass of KBr in the solution, multiply the mass of the solution by 15.0%:
Mass of KBr = 650.0 g × 15.0% = 650.0 g × 0.150 = 97.5 g
Step 2: Convert the percent concentration to a decimal.
The percent concentration is expressed as a percentage, but it needs to be converted to a decimal for further calculations. To convert 15.0% to a decimal, divide it by 100:
Percentage as a decimal = 15.0% ÷ 100 = 0.150
Step 3: Calculate the weight of KBr that can be recovered.
Since we are evaporating the solution to dryness, all the solvent (water in this case) will evaporate, leaving only the solute (KBr). Therefore, the weight of KBr that can be recovered is the same as the mass of KBr in the solution:
Weight of KBr recovered = 97.5 g
So, the weight of potassium bromide (KBr) that can be recovered by evaporating 650.0 g of a 15.0% KBr solution to dryness is 97.5 grams.