Question

In the lab, a chemist analyzed a sample of methanol and found that it was made of 7.3 g of carbon, 5.2 g of hydrogen, and 16.9 g of oxygen. What is the percent composition of each element?

a. Carbon: 40.1%, Hydrogen: 9.1%, Oxygen: 50.8%
b. Carbon: 50.8%, Hydrogen: 40.1%, Oxygen: 9.1%
c. Carbon: 9.1%, Hydrogen: 50.8%, Oxygen: 40.1%
d. Carbon: 40.1%, Hydrogen: 50.8%, Oxygen: 9.1%

Answer 1

To find the percent composition of each element, the mass of each element is divided by the total mass of the substance and then multiplied by 100. However, after calculating, none of the provided answer choices match the calculated percentages.

Step-by-step explanation:

To calculate the percent composition of each element in methanol, the mass of each element is divided by the total mass of the sample and then multiplied by 100 to find the percentage. First, the total mass of the methanol sample must be determined by adding the masses of carbon, hydrogen, and oxygen.

Total mass = 7.3 g (Carbon) + 5.2 g (Hydrogen) + 16.9 g (Oxygen) = 29.4 g

Next, we calculate the percent composition of each element:

• Carbon: (7.3 g / 29.4 g) × 100% = 24.8%
• Hygen: (5.2 g / 29.4 g) × 100% = 17.7%
• Oxygen: (16.9 g / 29.4 g) × 100% = 57.5%

After reviewing calculations, none of the given choices (a, b, c, d) match the calculated percentages, indicating a potential misunderstanding in the question or the answer choices provided.