If 33.7 grams of LiOH dissolve in enough water to make a 231-gram solution, what is the concentration in percent by mass?
LiOH + W = 231 grams
33.7 + W = 231
W = 197.3 Grams of water.
Concentration = LiOH/(W+LiOH) = 33.7/231
= 0.146 = 14.6%
To find the concentration of LiOH in percent by mass, we need to determine the mass of LiOH in the solution and express it as a percentage of the total mass of the solution.
To calculate the mass of LiOH in the solution, we subtract the mass of the water from the total mass of the solution:
Mass of LiOH = Total mass of solution - Mass of water
Total mass of solution = 231 grams
Mass of water = ?? (not given)
Since the question does not provide the mass of water, we should check if we can derive it from the given information.
The given information states that 33.7 grams of LiOH dissolves in enough water to make a 231-gram solution. This implies that the mass of LiOH (33.7 grams) plus the mass of the water will equal the total mass of the solution (231 grams):
Mass of LiOH + Mass of water = Total mass of solution
We can rearrange this equation to solve for the mass of water:
Mass of water = Total mass of solution - Mass of LiOH
Now we can fill in the values:
Mass of water = 231 grams - 33.7 grams
Calculate:
Mass of water = 197.3 grams
Now that we know the mass of water, we can find the mass of LiOH in the solution:
Mass of LiOH = Total mass of solution - Mass of water
Mass of LiOH = 231 grams - 197.3 grams
Calculate:
Mass of LiOH = 33.7 grams
Finally, we can calculate the concentration of LiOH in percent by mass:
Concentration = (Mass of LiOH / Total mass of solution) x 100
Plug in the values:
Concentration = (33.7 grams / 231 grams) x 100
Calculate:
Concentration ≈ 14.6 %
Therefore, the concentration of LiOH in the solution is approximately 14.6% by mass.