Final answer:
Molarity is calculated by dividing the number of moles of a solute by the volume of the solution in liters. To find the moles, convert the mass of the solute to moles using the molar mass. This process applies to all examples given, including cholesterol in serum, NH3 in ammonia, and isopropyl alcohol in rubbing alcohol.
Step-by-step explanation:
The concentration of a solution in molarity (M) is defined as the number of moles of solute per liter of solution. To calculate the molarity, you need the amount of solute in moles and the volume of the solution in liters. For example, to find the molar concentration of cholesterol
in human serum, you would first need to convert the mass of cholesterol (0.195 g) to moles using its molar mass. If the molar mass of cholesterol (C27H46O) is 386.65 g/mol, you would calculate the moles of cholesterol as 0.195 g / 386.65 g/mol, giving you the number of moles. Then, divide this number by the volume of the serum (0.100 L) to obtain the molarity.
The molarity formula is:
n (moles of solute) / V (liters of solution)
Applying a similar process to calculate the molarity of household ammonia and isopropyl alcohol in rubbing alcohol involves using their respective molar masses and the given masses and volumes.