Final answer:
To find the mass of butane in a 13.9% by mass solution of butane in hexane, calculate 13.9% of the total mass of the solution. Assuming hexane's density as 0.6548 g/mL, the mass of the 60.0 mL solution would be about 39.288 grams, and the mass of butane would be approximately 5.46 grams.
Step-by-step explanation:
To calculate the mass of butane contained in 60.0 ml of a 13.9% by mass solution of butane in hexane, we apply the definition of percent by mass. Percent by mass (also known as mass percent or mass/mass percent) is a way of expressing the concentration of a solution. This concentration measurement indicates the mass of solute (in this case, butane) as a percentage of the total mass of the solution.
First, we assume that the density of the solution is equivalent to that of hexane because it is the major component of the solution. Hexane has a density of about 0.6548 g/mL, but since a precise density value is not given, we will need to estimate based on this figure. The total mass of the solution can therefore be approximated as:
Mass of solution = volume of solution × density of solution
= 60.0 mL × 0.6548 g/mL
= 39.288 g (approximately)
To find the mass of butane, we take 13.9% of the total mass:
Mass of butane = 13.9% of total mass
= 0.139 × 39.288 g
= 5.4605 g (approximately)
Therefore, the mass of butane in the 60.0 mL solution is approximately 5.46 grams.