Question

use the following figure to answer the question.
a. 1 mole of the compound in the figure would weigh how many grams? (note: the atomic masses, in daltons, are approximately 12 for carbon, 1 for hydrogen, and 16 for oxygen). explain you answer.
b. identify the functional group in this molecule. is this molecule considered an acid or a base?

Explanation:

Step1: Count atoms in the molecule

The molecule has 2 carbon (C), 4 hydrogen (H) and 2 oxygen (O) atoms.

Step2: Calculate molar - mass of carbon

The atomic mass of carbon is 12 g/mol, and there are 2 carbon atoms. So the mass contributed by carbon is $2\times12 = 24$ g.

Step3: Calculate molar - mass of hydrogen

The atomic mass of hydrogen is 1 g/mol, and there are 4 hydrogen atoms. So the mass contributed by hydrogen is $4\times1=4$ g.

Step4: Calculate molar - mass of oxygen

The atomic mass of oxygen is 16 g/mol, and there are 2 oxygen atoms. So the mass contributed by oxygen is $2\times16 = 32$ g.

Step5: Calculate molar - mass of the compound

Add the masses of all elements together: $24 + 4+32=60$ g/mol. So 1 mole of the compound weighs 60 grams.

The functional group in the molecule is a carboxyl group (-COOH). A carboxyl group can donate a proton ($H^+$) in solution. According to the Brønsted - Lowry definition of acids (substances that donate protons), a molecule with a carboxyl group is an acid.

Answer:

a. 60 grams. The molecule has 2 C (2×12 = 24 g), 4 H (4×1 = 4 g) and 2 O (2×16 = 32 g), and 24 + 4+32 = 60 g.
b. The functional group is a carboxyl group (-COOH). The molecule is an acid because the carboxyl group can donate a proton ($H^+$) in solution.