Final answer:
To calculate the weight percent of ammonia in 3.33 m NH3(aq), multiply the molarity by the molecular weight of NH3, then divide by the mass of the solution, and multiply by 100. The correct answer is c) 5.67%.
Step-by-step explanation:
The question", concerns the calculation of the concentration of a solution in terms of weight percentage. To determine the weight percent of ammonia, the molecular weight of ammonia (NH3), which is 17.031 g/mol, and the definition of molarity (mol/L) are needed. For a 3.33 molarity (M) ammonia solution, this means there are 3.33 moles of ammonia in 1 liter of solution.
To find the weight percent, multiply the number of moles of ammonia (3.33) by the molecular weight (17.031 g/mol) to find the mass of ammonia in grams per liter. Then, since solutions are typically assumed to have a density close to that of water, we can reasonably approximate 1 liter of solution to have a mass of about 1000 grams. Once we have the mass of ammonia, we divide it by the total mass of the solution (1000 g), and then multiply by 100 to get the weight percent.
Calculation:
Mass of NH3 = 3.33 moles * 17.031 g/mol = 56.71323 grams
Weight percent = (56.71323 g NH3 / 1000 g solution) * 100 = 5.67%
Therefore, the correct answer is c) 5.67%.