Calculate the number of carbon atoms in 76.91 g of benzoic acid, C₆H₅COOH.

Question

Quizplus · Accepted Answer

To calculate the number of carbon atoms in benzoic acid, we need to first calculate the molar mass of benzoic acid (C7H6O2):

Molar mass of C = 12.01 g/mol
Molar mass of H = 1.01 g/mol
Molar mass of O = 16.00 g/mol

Total molar mass of benzoic acid:
(7 x molar mass of C) + (6 x molar mass of H) + (2 x molar mass of O)
= (7 x 12.01) + (6 x 1.01) + (2 x 16.00)
= 122.12 g/mol

Now, we can use the following formula to calculate the number of moles of benzoic acid in 76.91 g:

Number of moles = mass ÷ molar mass
= 76.91 ÷ 122.12
= 0.63 mol

Finally, we can use the chemical formula of benzoic acid to calculate the number of carbon atoms:

Number of carbon atoms = number of moles x number of carbon atoms in one molecule
= 0.63 x 7
= 4.41

Therefore, the number of carbon atoms in 76.91 g of benzoic acid is approximately 2.655 × 10^24. The closest option to this answer is option C.

Calculate the Number of Carbon Atoms in 76