Question

Determine the percent composition of salicylic acid, C₇H₆O₃?

The molar mass of C₇H₆O₃ is 138.1g/mol.
O 60.88% C, 4.379% H, 34.76% O
O 65.34% C, 6.271% H, 28.39% O
O 52.34% C, 5.762% H, 41.89% O
O 62.81% C, 3.274% H, 33.92% O

Answer 1

The percent composition of salicylic acid (C7H6O3) is approximately 60.86% Carbon, 4.38% Hydrogen, and 34.76% Oxygen, calculated by determining the molar mass of the compound and then finding the percent by mass of each element.

Step-by-step explanation:

To determine the percent composition of salicylic acid (C7H6O3), you first calculate the molar mass of salicylic acid. The molar mass is the sum of the atomic masses of all the atoms in the molecular formula. Using the atomic masses of carbon (12.01 g/mol), hydrogen (1.008 g/mol), and oxygen (16.00 g/mol), calculate as follows:

7 atoms of Carbon: 7 × 12.01 g/mol = 84.07 g/mol

6 atoms of Hydrogen: 6 × 1.008 g/mol = 6.048 g/mol

3 atoms of Oxygen: 3 × 16.00 g/mol = 48.00 g/mol

Adding these together gives the molar mass of salicylic acid:

84.07 g/mol + 6.048 g/mol + 48.00 g/mol = 138.118 g/mol

Then you calculate the percent by mass of each element using their individual masses divided by the molar mass multiplied by 100%:

Percent Carbon (C): (84.07 g/mol ÷ 138.118 g/mol) × 100% = 60.86%
Percent Hydrogen (H): (6.048 g/mol ÷ 138.118 g/mol) × 100% = 4.38%
Percent Oxygen (O): (48.00 g/mol ÷ 138.118 g/mol) × 100% = 34.76%

Therefore, the percent composition of salicylic acid is approximately 60.86% Carbon, 4.38% Hydrogen, and 34.76% Oxygen.