Question

select the model of a molecule composed of one carbon atom, two hydrogen atoms, and two oxygen atoms
formic acid ethanol methanol
which is the chemical formula for the substance composed of these molecules?
c₃h₆o₂ c₂h₆o ch₂o

Explanation:

Part 1: Selecting the correct molecular model

The molecule has 1 C, 2 H, and 2 O atoms. Let’s analyze each model:

• Formic acid: Contains 1 C, 2 O, and 2 H (matches atom counts: C=1, H=2, O=2).
• Ethanol: Has 2 C atoms (too many, we need 1 C).
• Methanol: Has 1 C, 1 O, and 4 H (O count is 1, not 2).

Thus, the formic acid model (first one) is correct.

Step 1: Identify atom counts

The molecule has 1 carbon (C), 2 hydrogen (H), and 2 oxygen (O) atoms.

Step 2: Write the formula

Using the atom counts, the formula is $CH_2O_2$ (since C=1, H=2, O=2; subscripts are omitted for 1, so $CH_2O_2$).

Answer:

The first model (labeled "formic acid")

Part 2: Determining the chemical formula