A typical deposit of cholesterol, C₂₇H₄₆O, in an artery has a mass of 3.90 mg. How many molecules of cholesterol are present in this deposit?

Question

Quizplus · Accepted Answer

To calculate the number of molecules, we first need to find the molecular weight of cholesterol. The molecular weight of cholesterol is 386.65g/mol.

Now, convert the mass of the deposit to grams (3.90 mg = 0.00390 g) 
Next, use the formula number of molecules = mass / molecular weight 
= 0.00390 g / 386.65 g/mol 
= 1.01 x 10^(-5) moles

Finally, convert moles to molecules, using Avogadro's number: 
= 1.01 x 10^(-5) moles * 6.022 x 10^23 molecules/mole 
= 6.07 x 10^18 molecules

Therefore, the answer is B, 6.07 × 10^18.

A Typical Deposit of Cholesterol, C27H46O, in an Artery Has

A Typical Deposit of Cholesterol, C₂₇H₄₆O, in an Artery Has